1. Rutin trihydrate liposomes were formulated using the thin film hydration method to enhance topical delivery of the antioxidant rutin trihydrate.
2. The liposomes were characterized for parameters like entrapment efficiency, vesicle size, and zeta potential. The optimized formulation showed 88% entrapment efficiency.
3. In vitro and ex vivo release studies showed that the rutin trihydrate liposomal gel provided prolonged drug release over 12 hours and exhibited anti-elastase activity, demonstrating its potential for topical delivery applications.
Formulation and evaluation ofmetformin HCl micro beads by ionotropic gelation...Sagar Savale
The Metformin HCL Micro Beads is formulated by the Ionotropic Gelation Method. The CMC is a Swellable
polymer is responsible for the Sustained release action or activity. A combination of CMC (Carboxy Methyl
Cellulose) and Sodium Alginate shows better sustained release activity. The PreparedSustained released Micro
Beadsis Evaluated In terms of bulk density, tapped density, angle of repose, Carr’s Index, Swelling Index, Drug
Content, % Encapsulation Efficiency and vitro study. The result associated in Optimized batch is good to
Satisfactory and having a good free flowing property. The Drug Content and % Encapsulation Efficiency values are
within the pharmacopeia limit. The in vitro Dissolution studies shows Maximum percentage of release of drug
(71.15) with in end of 4 Hours.
Formulation and evaluation ofmetformin HCl micro beads by ionotropic gelation...Sagar Savale
The Metformin HCL Micro Beads is formulated by the Ionotropic Gelation Method. The CMC is a Swellable
polymer is responsible for the Sustained release action or activity. A combination of CMC (Carboxy Methyl
Cellulose) and Sodium Alginate shows better sustained release activity. The PreparedSustained released Micro
Beadsis Evaluated In terms of bulk density, tapped density, angle of repose, Carr’s Index, Swelling Index, Drug
Content, % Encapsulation Efficiency and vitro study. The result associated in Optimized batch is good to
Satisfactory and having a good free flowing property. The Drug Content and % Encapsulation Efficiency values are
within the pharmacopeia limit. The in vitro Dissolution studies shows Maximum percentage of release of drug
(71.15) with in end of 4 Hours.
Formulation and In-Vitro Evaluation of Fluconazole Loaded Microsponge Gel For...iosrjce
IOSR Journal of Pharmacy and Biological Sciences(IOSR-JPBS) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of Pharmacy and Biological Science. The journal welcomes publications of high quality papers on theoretical developments and practical applications in Pharmacy and Biological Science. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Formulation and evaluation of mucoadhesive tablets of carvedilol using natura...Nausheen Fatima
Present work describes formulation and evaluation mucoadhesive tablets of Carvedilol using natural binders such as Chitosan and Guar Gum to reduce the first pass metabolism and frequency of administration.
Formulation and evaluation of microspheres with aceclofenacSagar Savale
Aceclofenac is an analgesic and anti-inflammatory drug that reduces fever, pain, and inflammation in rheumatoid
arthritis, osteoarthritis and ankylosing spondylitis. Aceclofenac has higher anti-inflammatory action than
conventional NSAIDs. Development of microspheres is a promising technology for controlled release and drug
targeting. Various types of microspheres such as bio-adhesive, magnetic, floating, radioactive and polymeric
microspheres are developed for various purposes. Microspheres occupied a central place in novel drug delivery, it
can targeted and localized drug delivery system. This Aceclofenac Microsphere is Prepared by using Spray drying
Technique in which release rate of drug is mainly depends on formulation composition (Eudragit RS 30 D and
Ethyl Cellulose (1:2 ratio)). Formulated microspheres were characterized for particle size, encapsulation efficiency
and In vitro studies. The optimum drug-to-polymer ratio and feed flow rate is responsible for higher percent yield,
smaller particle size and maximum encapsulation efficiency.
formulation and evaluation of microbeadsgurleen kaur
Microencapsulation has been employed to sustain the drug release, reduce or eliminate drug related adverse effects, dose intake and improve the bioavailability inspite drug undergo extensive first pass metabolism ultimately improve the compliance in pharmacotherapy of inflammation and pain.
Microencapsulation by ionotropic gelation technique is one of the widely used method for preparation of calcium alginate beads which has ability to form gels reaction with calcium salts .
Microencapsulation has been employed to sustain the drug release, reduce or eliminate drug related adverse effects, dose intake and improve the bioavailability inspite drug undergo extensive first pass metabolism ultimately improve the compliance in pharmacotherapy of inflammation and pain.
Microencapsulation by ionotropic gelation technique is one of the widely used method for preparation of calcium alginate beads which has ability to form gels reaction with calcium salts .
Formulation and evaluation of Muco adhesive Buccal Tablets of Ramprildoddaapurupa
The buccal mucosa lines the inner cheek and Buccal formulations are placed in the mouth between upper gingiva(gums) and cheek to treat local and systemic conditions.
Drugs which undergoes Extensive first pass metabolism and drug degradation in acidic media, GI tract can be administered through buccal route.
The oral cavity has been used as a site for local and systemic drug delivery.
PRONIOSOMES- A NOVEL VESICULAR DRUG DELIVERY SYSTEMAbhijeet Waghare
Proniosomes are dry formulations of surfactant coated carrier, which can be measured out as needed and rehydrated by brief agitation in water. These “Proniosomes” minimizes problems of niosome physical stabilty such as, aggregation, fusion and leaking and leaking of entrapped drug, and provided additional convenience in transportation, distribution, storage and dosing, and hydrolysis of encapsulated drugs. Also handling and storage of surfactants require no special conditions.
MICROSPONGE: A NOVEL APPROACH IN GASTRO-RETENTION DRUG DELIVERY SYSTEM (GRDDS)Snehal Patel
Oral controlled release dosage forms face several physiological restriction like inability to retain and position the controlled drug delivery system within the targeted region of the gastrointestinal tract (GIT) due to fluctuation in gastric emptying. This results in non‑uniform absorption pattern, inadequate medication release and shorter residence time of the dosage form in the stomach. As the fallout of this episode there is inadequate absorption of the drug having absorption window predominantly, in the upper area of GIT. These contemplations have provoked to the development of oral controlled release dosage forms with gastroretentive properties. Microsponge hold certification as one of the potential approaches for gastric retention. Microsponge are porous spherical empty particles without core and can remain in the gastric region for delayed periods. They significantly increase the gastric residence time of medication, thereby enhance bioavailability, improves patient compliance by reducing dosing frequency, lessen the medication waste, enhance retention of medication which solubilize only in stomach, enhance solubility for medications that are less soluble at a higher pH environment. In the present review method of preparation, characterization, advantages, disadvantages and applications of floating microsponge are discussed. Please cite
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Formulation and In-Vitro Evaluation of Fluconazole Loaded Microsponge Gel For...iosrjce
IOSR Journal of Pharmacy and Biological Sciences(IOSR-JPBS) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of Pharmacy and Biological Science. The journal welcomes publications of high quality papers on theoretical developments and practical applications in Pharmacy and Biological Science. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Formulation and evaluation of mucoadhesive tablets of carvedilol using natura...Nausheen Fatima
Present work describes formulation and evaluation mucoadhesive tablets of Carvedilol using natural binders such as Chitosan and Guar Gum to reduce the first pass metabolism and frequency of administration.
Formulation and evaluation of microspheres with aceclofenacSagar Savale
Aceclofenac is an analgesic and anti-inflammatory drug that reduces fever, pain, and inflammation in rheumatoid
arthritis, osteoarthritis and ankylosing spondylitis. Aceclofenac has higher anti-inflammatory action than
conventional NSAIDs. Development of microspheres is a promising technology for controlled release and drug
targeting. Various types of microspheres such as bio-adhesive, magnetic, floating, radioactive and polymeric
microspheres are developed for various purposes. Microspheres occupied a central place in novel drug delivery, it
can targeted and localized drug delivery system. This Aceclofenac Microsphere is Prepared by using Spray drying
Technique in which release rate of drug is mainly depends on formulation composition (Eudragit RS 30 D and
Ethyl Cellulose (1:2 ratio)). Formulated microspheres were characterized for particle size, encapsulation efficiency
and In vitro studies. The optimum drug-to-polymer ratio and feed flow rate is responsible for higher percent yield,
smaller particle size and maximum encapsulation efficiency.
formulation and evaluation of microbeadsgurleen kaur
Microencapsulation has been employed to sustain the drug release, reduce or eliminate drug related adverse effects, dose intake and improve the bioavailability inspite drug undergo extensive first pass metabolism ultimately improve the compliance in pharmacotherapy of inflammation and pain.
Microencapsulation by ionotropic gelation technique is one of the widely used method for preparation of calcium alginate beads which has ability to form gels reaction with calcium salts .
Microencapsulation has been employed to sustain the drug release, reduce or eliminate drug related adverse effects, dose intake and improve the bioavailability inspite drug undergo extensive first pass metabolism ultimately improve the compliance in pharmacotherapy of inflammation and pain.
Microencapsulation by ionotropic gelation technique is one of the widely used method for preparation of calcium alginate beads which has ability to form gels reaction with calcium salts .
Formulation and evaluation of Muco adhesive Buccal Tablets of Ramprildoddaapurupa
The buccal mucosa lines the inner cheek and Buccal formulations are placed in the mouth between upper gingiva(gums) and cheek to treat local and systemic conditions.
Drugs which undergoes Extensive first pass metabolism and drug degradation in acidic media, GI tract can be administered through buccal route.
The oral cavity has been used as a site for local and systemic drug delivery.
PRONIOSOMES- A NOVEL VESICULAR DRUG DELIVERY SYSTEMAbhijeet Waghare
Proniosomes are dry formulations of surfactant coated carrier, which can be measured out as needed and rehydrated by brief agitation in water. These “Proniosomes” minimizes problems of niosome physical stabilty such as, aggregation, fusion and leaking and leaking of entrapped drug, and provided additional convenience in transportation, distribution, storage and dosing, and hydrolysis of encapsulated drugs. Also handling and storage of surfactants require no special conditions.
MICROSPONGE: A NOVEL APPROACH IN GASTRO-RETENTION DRUG DELIVERY SYSTEM (GRDDS)Snehal Patel
Oral controlled release dosage forms face several physiological restriction like inability to retain and position the controlled drug delivery system within the targeted region of the gastrointestinal tract (GIT) due to fluctuation in gastric emptying. This results in non‑uniform absorption pattern, inadequate medication release and shorter residence time of the dosage form in the stomach. As the fallout of this episode there is inadequate absorption of the drug having absorption window predominantly, in the upper area of GIT. These contemplations have provoked to the development of oral controlled release dosage forms with gastroretentive properties. Microsponge hold certification as one of the potential approaches for gastric retention. Microsponge are porous spherical empty particles without core and can remain in the gastric region for delayed periods. They significantly increase the gastric residence time of medication, thereby enhance bioavailability, improves patient compliance by reducing dosing frequency, lessen the medication waste, enhance retention of medication which solubilize only in stomach, enhance solubility for medications that are less soluble at a higher pH environment. In the present review method of preparation, characterization, advantages, disadvantages and applications of floating microsponge are discussed. Please cite
EESPL provides the best android training in Chandigarh. As Android is one of the fastest growing industry in IT Sector . The IT organisation wants qualified and experience candidates to take over the task . EESPL provides the quality and the Experience to get in the field of android development .
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In this ppt ,i have covered the introduction of microspheres,various preparation methods of microspheres, advantages and disadvantage of microspheres,types and evaluation parameters of the microspheres.
Formulation Development and In Vitro Evaluation of Microsponge Drug Delivery ...YogeshIJTSRD
A Microsponge Delivery System MDS is patented, highly cross linked, porous, polymeric microspheres that can entrap wide range of actives and then release them onto the skin over a time and in response to trigger. It is a unique technology for the controlled release of topical agents and consists of microporous beads, typically 10 25 microns in diameter, loaded with active agent. In this study, Ketoconazole microsponges were prepared by using quasi emulsion solvent diffusion method. The microsponges thus prepared, were evaluated for production yield, loading efficiency, particle size analysis, in vitro release study of microsponges, and stability. Hence, the present work concluded that MDS has a great potential in topical delivery of drugs like Ketoconazole, with added advantage of reduction in irritation profile due to the controlled release and possible enhancement in the activity due to amorphization of the drug. Vilas S. Bhagat | Sanjay R. Arote "Formulation Development and In-Vitro Evaluation of Microsponge Drug Delivery System of Antifungal Drug" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-3 , April 2021, URL: https://www.ijtsrd.com/papers/ijtsrd39870.pdf Paper URL: https://www.ijtsrd.com/pharmacy/pharmaceutics/39870/formulation-development-and-invitro-evaluation-of-microsponge-drug-delivery-system-of-antifungal-drug/vilas-s-bhagat
ABSTRACT Gliclazide microspheres were prepared by ionotropic gelation method using bioadhesive polymers such as sodium alginate, carbopol 934, carbopol 971, HPMC K4M in different ratios. Totally twelve different formulations of gliclazide were prepared by using the above polymers. The microspheres were characterized for drug content, entrapment efficiency, swelling index, mucoadhesive property by In vitro wash-off test and in-vitro drug release. The results of this investigation indicate that ionic cross linking technique Ionotropic gelation method can be successfully employed to fabricate Model drug microspheres. Micrometric studies revealed that the mean particle size of the prepared microspheres was in the size range of 512-903 μm and are suitable for bioadhesive microspheres for oral administration. The in-vitro mucoadhesive study demonstrated that microspheres of Model drug using sodium alginate along with Carbopol 934 as copolymer adhered to the mucus to a greater extent than the microspheres of Model drug using sodium alginate along with Carbopol 971 and HPMC K4Mas copolymers. Analysis of drug release mechanism showed that the drug release from the formulations followed non-Fickian diffusion and the best fit model was found to be Korsmeyer-Peppas. Based on the results of evaluation tests formulation coded T4 was concluded as best formulation. Keywords: Bioadhesive Microspheres, Gliclazide, Ionotropic gelation method.
Transfersome: A Novel Vesicular Carrier to Enhance Permeation of Flurbiprofen...VaibhavBhagwat13
Transfersome is novel and advance form of Liposome. Due to its flexibility (highly deformable) and self-optimizing drug carrier vesicles passage across the skin.
Formulation and Evaluation of Liquisolid Compact of Etoricoxib for Solubility...ijpsmjournal
Liquisolid compact technique is a novel concept for delivery of drug through oral route. This
approach of delivering drug is mostly suitable for lipophilic drug and poorly or water insoluble drugs. The
main objective of present study was to increase the solubility of water in soluble BSc class II drug etoricoxib.
Etoricoxib is alipophilic drug that is practically insoluble in water and exhibit an excessively slow dissolution
rate in class II compound in biopharmaceutics classification system. The liquid solid compacts were prepared
using PEG 400 as non volatile solvent, microcrystalline cellulose as carrier, aerosil 200 as coating material
and Sodium starch glycolate was used as super disintegrating agent. Several formulations of liquid solid
compacts having different drug concentration in PEG 400 (non volatile solvent) with varying ratio of career
to coating material were prepared. The liquid solid compacts were evaluated for Bulk characterization, Flow
properties, solubility studies, drug content, FTIR studies, DSC studies and in vitro drug release studies. The
saturated solubility studies and in vitro drug release studies shows that the increase in solubility of drug and
enhanced drug release rate in liquisolid compacts compared to pure drug. The Formulation F5 andF4 is
considered as best formulation as it has shown highest drug release in short time (1 hr). Our studies showed
that the solubility of the drug can be significantly enhanced with increase in the carrier content there is
increase in the solubility resulting and enhanced drug release rate.
Similar to Formulation of Rutin trihydrate Liposomes for Topical Delivery (20)
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
263778731218 Abortion Clinic /Pills In Harare ,sisternakatoto
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- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
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These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Formulation of Rutin trihydrate Liposomes for Topical Delivery
1. International Journal of Pharmaceutical Research | July – Sept 2015 | Vol 7 | Issue 3|29
Research Article
Formulation and Characterization of Rutin trihydrate
Liposomes for Topical Delivery
APARAJITA VARSHNEYA
AND PADMINI RAVIKUMAR
Department of Pharmaceutics, SVKM’s Dr. Bhanuben Nanavati College of Pharmacy,
Gate No: 1, Mithibai College Campus, V.M. Road, Vile Parle (W), Mumbai-400 056, India
ABSTRACT
In the present study, liposomes were formulated as drug carriers for enhancing the delivery of an antioxidant Rutin
trihydrate for topical administration. Formulation of liposomes was done by thin film hydration method. Optimization
was achieved by varying the lipid to cholesterol ratio and gradually increasing the amount of drug until maximum
entrapment efficiency was achieved. The formulation and process parameters were optimized to attain multilamellar
liposomes with homogeneous size and good entrapment. The optimized batch gave entrapment efficiency of 88%.
Gels were prepared by using Carbopol 940 as the gelling agent. The in vitro and ex vivo release profile of liposomal gels
was compared with conventional gel formulations. The liposomal gel showed prolonged drug release upto 12 h and
also exhibited anti-elastase activity. The safety of liposomal gels was ensured by conducting skin irritation studies on
albino Wistar rats.
Keywords: Liposomes, Rutin trihydrate, topical delivery, gels.
Address for correspondence
Aparajita Varshneya, SVKM’s Dr. Bhanuben Nanavati College of Pharmacy, Gate No.1, Mithibai, College Campus, V.M.
Road, Vile Parle (West), Mumbai ‐ 400 056, India.
Phone no: +91‐9870687261 e‐mail: aparajita.varshney@yahoo.com
Received:18/02/15, Revised:02/04/15, Accepted:18/04/15
INTRODUCTION
Topical drug delivery has long been sought after, as
it is coupled with well-established advantages like
localised drug delivery, avoidance of first pass
metabolism, improved patient compliance owing to
its non-invasive nature and reduced systemic side
effects [1]. Despite these merits, the brick and mortar
structure of stratum corneum i.e. the horny layer
serves as the principal barrier to the percutaneous
absorption of drugs [2,3]. Owing to these barrier
properties of the skin, the delivery of active
substances from conventional formulations is
generally compromised. Thus, there arises the need
for a suitable carrier to enhance drug delivery [4].
Liposomes
Liposomes were first described by British
haematologist Dr. Alec D Bangham in early 1960’s
[5]. Liposomes are highly organized structures,
composed of concentric bi-layered vesicles in which
an aqueous volume is enclosed by a membranous
lipid bilayer [6]. The main advantages that have
made these vesicular systems favourable for drug
delivery are their tissue compatibility,
biodegradability, safety and their ability to entrap
almost any drug in the bilayer core or in the outer
domain. Additionally, liposomal drug formulations
can be used to overcome a drug’s non-ideal
properties and unfavourable pharmacokinetic
profiles [7]. Regarding topical application, liposomes
offer a wide range of advantages including
moisturization and prolonged dermal release [8].
Topical use of antioxidants has been adopted as an
important strategy in cosmeceutical industry to avoid
wrinkling of the skin and protect it from degenerative
effects such as photoaging, sunburn,
photocarcinogenesis etc. [9]. Antioxidants help in
preventing and repairing damage caused due to
oxidative stress. They scavenge free radicals which
are postulated to be the mediators in skin aging [10].
They are found to be useful in delaying the signs of
aging such as fine lines, wrinkles and age spots.
Antioxidants are promising in photoprotection with
negligible side effects at physiological concentrations
[11]. Of the various antioxidants, bioflavonoids are
one of the most powerful antioxidants. They are a
class of plant secondary metabolites possessing a
broad range of pharmacological activities. Rutin
trihydrate was chosen as the active molecule as it is a
powerful antioxidant which inhibits free-radical
mediated cytotoxicity and lipid peroxidation. It is
sparingly soluble in water (0.125 g/L). This limits its
use in topical delivery. Thus liposomes were chosen
as drug carriers as they are amphiphilic in nature
and lipophilic molecules get embedded in their
concentric bilayers. Liposomes being physiologically
similar to cell membrane, are nontoxic in nature and
are easily re-absorbed from the epidermis into the
deepest layers [12]. Thus, the objective of the study
was to enhance the accumulation of drug at the site
of administration and achieve prolonged release by
means of liposomal formulation.
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30 | International Journal of Pharmaceutical Research | July – Sept 2015 | Vol 7 | Issue 3
MATERIALS AND METHODS
Phosphatidylcholine (Leciva S-70) was a generous
gift sample from VAV Life Sciences, Mumbai, India.
Rutin trihydrate was purchased from Loba Chemie,
Mumbai and Cholesterol was procured from
Qualigens, Mumbai. Carbopol 940, Glass beads
(2.5 mm-3.5 mm) and all other AR grade reagents
were purchased from S D Fine-Chem Ltd., Mumbai.
Dialysis membrane 150 was purchased from
HiMedia Laboratories Pvt. Ltd., Mumbai and porcine
skin was procured from local market. Healthy male
albino Wistar rats (Rattus norvegicus sp.) were
purchased from Bharat Serum, Mumbai, India.
Liposomes were prepared using Rotary Evaporator,
Roteva, Equitron and UV-visible spectrophotometer,
Shimadzu 1800 was used for evaluation.
I. Preparation of Rutin Trihydrate Liposomes:
Multilamellar vesicles were prepared by thin film
hydration technique as described by Bangham et al.
[13]. Phosphatidylcholine, Cholesterol and Rutin
trihydrate constituted the lipid mixture. This lipid
mixture was dissolved in chloroform and methanol
(2:1) in a round bottom flask (RBF) and 25 g glass
beads were added for homogeneous film formation.
The RBF was attached to the rotary flash evaporator
(Roteva, Equitron) and allowed to rotate at 80 r/min
in a thermostated water bath at 40°. The organic
solvents were then removed by slow application of
vacuum leading to lipid film formation on the walls
of the flask. The film was allowed to dry for 60 min
to ensure complete removal of solvent. The dried
lipid film was hydrated with phosphate buffer (pH:
5.4) at 150 r/min and 46° that is above the transition
temperature of lipid. Rotation was continued for 30
min. The Rutin trihydrate liposomal suspension was
kept at room temperature for 2 h for complete
hydration and for annealing structural defects.
The liposomes produced by this method are large
and heterogeneous in size, thus they were downsized
by bath sonication for 20 min. The suspension was
also vortexed for few minutes. The liposomal
suspension was characterized for physical
appearance, settling time, re-dispersion
time, entrapment efficiency and vesicle size by optical
microscopy. It was then filled in amber colored glass
bottles and stored at 4° until further use.
II. Characterization of Liposomes:
Rutin trihydrate liposomes were characterized for
following parameters:
Optical Microscopy
A drop of the liposomal suspension was placed on a
clean glass slide and observed under high power
45x and 100x of the optical microscope (Motic
microscope). Multilamellar vesicles (MLV) were
clearly identified (Figure 1). Microscopic observations
were used to study presence of aggregates,
precipitation or leakage of drug. Size and shape of
the vesicles was noted for all liposomal batches.
Figure 1: (a) Large multilamellar vesicles as
visible under 100x magnification
Determination of Vesicle Entrapment Efficiency
Entrapment efficiency for the batches prepared
during the optimization process was estimated by the
following procedure:
The liposomal pellet i.e. the drug loaded liposomes
were separated from the aqueous phase by
centrifugation at 15,000 r/min using Microspin
centrifuge for 30-45 min until a clear supernatant
was obtained. The amount of drug loaded was
estimated by both direct and indirect method.
Direct method: After centrifugation, the supernatant
was decanted. The formed pellet was washed with
phosphate buffer and vortexed, in order to remove
the free drug adsorbed on the surface of liposomes.
This step was repeated thrice to completely separate
the unentrapped drug. The resulting pellet was then
dissolved in methanol and sonicated for 20 min.
(This causes rupturing of pellet and release of
entrapped drug in the solution). The resulting
methanolic solution was then analyzed by UV
spectrophotometry using the developed analytical
method.
% Entrapment Efficiency (E.E.) =
(Amount of drug quantified in the pellet) x 100
Total amount of drug added
Indirect method: The supernatant of the liposomal
dispersion decanted after centrifugation and the
solutions collected after washing of pellet were
combined and analyzed by developed UV
spectrophotometric method for the amount of drug
present. % Entrapment efficiency was estimated as
follows:
% Entrapment Efficiency (E.E) =
(Total amount of drug added - Amount of drug
detected in the supernatant) x 100_
Total amount of drug added
Determination of vesicle size and size distribution
Vesicle size was determined by dynamic light
scattering using a computerized inspection system
(Malvern particle size analyzer). Freshly prepared
batches of vesicles were diluted ten-fold with filtered
3. Aparajita Varshneya et al /Formulation and Characterization of Rutin Liposomes
International Journal of Pharmaceutical Research | July – Sept 2015 | Vol 7 | Issue 3|31
distilled water and then analyzed at 25° using ten
runs at each scan. Optimization time was fixed at
120 s. Vesicle size and polydispersity index were
measured for the liposomal formulation. The
measurements were done in triplicate.
Zeta potential measurement
Liposomal suspension was diluted with filtered
distilled water and zeta potential was measured in
triplicate with the help of Malvern zetasizer.
Transmission Electron Microscopy (TEM)
TEM analysis was carried out for optimized drug
loaded liposomal suspension. A drop of the diluted
formulation was placed with the aid of a micropipette
on a coated copper grid 3 mm in diameter. Negative
staining was carried out by uranyl acetate. The grid
was allowed to dry under an IR lamp for about 20
min. The grid was then loaded on a probe which was
inserted in the slot designed for it in the electron
microscope. The grid containing the sample was then
bombarded with electrons accelerated at 200 kV and
the sample visualized over a fluorescent stage.
Vesicle size of the sample was measured and marked
and its morphology observed on the computer
(Figure 2).
Figure 2: Negative staining TEM imaging of Rutin
trihydrate liposomesMagnification 100,000x (size
approx. 600 nm)
III. Optimization of Process and Formulation
Parameters:
Many factors influence the formation of liposomes
and its characteristics. Therefore, the following
process parameters were optimized to obtain
liposomes with maximum entrapment efficiency,
homogeneous size and stability.
a. Process Parameters
Speed of the rotary evaporator
It is desirable to obtain a thin and uniform film as it
governs the final output of liposomal preparation.
The speed of rotation was varied from 60 r/min to
150 r/min during film formation as well as during
hydration.
The ratio and volume of solvent system
The solvent system was optimized by taking various
combinations of organic solvents i.e. chloroform and
methanol. The ratios 1:1, 2:1 and 3:1 were tried and
the film was evaluated in terms of its uniformity.
Quantity of glass beads
Thin film hydration technique is readily employed for
its feasibility on a laboratory scale, but problems
related to limitations of surface area exist. Glass
beads are commonly used for this purpose which
helps to increase the surface area to provide a thin
film. Liposomal dispersions were prepared using
different ratios of glass beads (diameter: 2.5 mm-3.5
mm) and solvent volume such as 0:1, 2:1, 3:1 and
4:1. The formulations were evaluated in terms of
uniformity of film and separation of vesicle
aggregates (microscopic observation).
Vesicle sizing technique
Size reduction of the vesicles is done to obtain a
homogeneous population of vesicles with low
polydispersity index. The various techniques studied
for size reduction were bath sonication using
ultrasonic bath, high pressure homogenization and
by using ultra turrax. Bath sonication was carried out
at room temperature for 20-30 min. Size reduction
using Ultra turrax was done at 6000 r/min for 15
min. High pressure homogenization was also tried by
carrying out approximately 10 cycles at a pressure of
5000 psi for 10 min. The effect of these techniques
was studied by estimating entrapment efficiency,
vesicle size and polydispersity index.
pH of the hydrating media
The effect of pH of the phosphate buffer was studied
on the formulation. The effect of pH on the
entrapment of the drug is related to its pKa. Hence
the pH of the hydrating buffer was adjusted at values
closer to the pKa of the drug and entrapment
efficiency was estimated. Distilled water, phosphate
buffer pH 5.4, 6.8 and 7.4 were used as hydrating
media and formulations were studied in terms of
colour, sedimentation, redispersibility and
entrapment efficiency.
Table 1: Formula optimization based on lipid concentration
Lipid Conc. (%) Consistency Settling rate Redispersibility
Vesicle size
(μ)
0.5 Thin suspension +++ + 1-4
1
Moderate, smooth
suspension
++ +++ 0.25-3
2 Thick suspension + ++ 2-6
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32 | International Journal of Pharmaceutical Research | July – Sept 2015 | Vol 7 | Issue 3
Settling rate: + Slow ++ Moderate +++Fast Redispersibility + Poor ++ Good
+++Excellent
Table‐2: Formula optimization based on Drug: Lipid and PC: CH ratio
Batch No.
PC:CH
(molar
ratio)
Total lipid: 100 mg
Globule Size
(μ)
EE
(%)Amount of PC
(mg)
Amount of CH
(mg)
B1 1:0 100 0 0.5-5 56
B2 1:0.2 90.75 9.25 0.5-1.5 88
B3 1:0.5 79.68 20.32 0.5-3 79
B4 1:1 66.21 33.79 0.25-3.5 74
B5 1:0.1 95.15 4.85 1-4 49
B6 1:0.2 90.75 9.25 1-3 53
B7 1:0.5 79.68 20.32 2-4.5 58
B8 1:1 66.21 33.79 1-5 51
B9 1:0.1 95.14 4.85 1-5 33
B10 1:0.2 90.75 9.25 2-5 41
B11 1:0.5 79.68 20.32 2-4 35
B12 1:1 66.21 33.79 1-6 39
PC: Phosphatidylcholine, CH: Cholesterol, EE: Entrapment Efficiency
Formulation parameters
The basic components of formulation such as
lipid concentration, drug to lipid ratio and
phosphatidylcholine to cholesterol ratio were
optimized to obtain reproducibility in the quality
of liposomes. The key parameters considered for
optimization of formula were entrapment
efficiency and vesicle size. Percent drug
entrapment i.e. the amount of drug inside the
vesicles is the most important parameter for
liposomal formulations.
Lipid Concentration
Liposomal formulations were prepared with
increasing concentration of phosphatidylcholine
0.5%, 1% and 2% i.e. the quantity of lipid taken
was 50 mg, 100 mg and 200 mg for 10 ml
liposomal batch. Rutin trihydrate at low, fixed
concentration was incorporated in the
formulations. The formulations were studied on
the basis of physical observations such as
consistency, settling rate, redispersibility and
vesicle size.
Drug to Lipid ratio
This is an important factor that determines the
amount of drug entrapped within the liposomes.
It varies as per the drug, its molecular size,
charge and physical properties. For lipid soluble
drugs, larger quantities of drug can be
encapsulated and hence drug to lipid ratio can be
large. Water soluble drugs have limitations of
encapsulation efficiency, as comparatively smaller
volume of aqueous portion is available for
entrapment.
Phosphatidylcholine to cholesterol ratio
Liposomes were formulated in different molar
ratios of phosphatidylcholine and cholesterol, with
increasing concentration of drug and parameters
such as % entrapment efficiency and globule size
were estimated.
IV. Preparation of Liposomal Gels
Rutin trihydrate lipogel was prepared by using
Carbopol 940 gel base. Carbopol is a pH
sensitive polymer and gel formation occurs after
inducing neutralization. Definite amount of
Carbopol 940 was kept for hydration in double
distilled water containing preservatives overnight.
Liposomal pellet (obtained after centrifugation
and separation of unentrapped drug) was
dispersed in distilled water by sonication and
added to hydrated Carbopol solution with stirring.
Gelling was induced by neutralization using
triethanolamine. The gels were evaluated for their
visual appearance, colour, texture, feel upon
application (like greasiness, smoothness), pH,
viscosity, spreadability, drug content and in
vitro/ex vivo drug release.
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International Journal of Pharmaceutical Research | July – Sept 2015 | Vol 7 | Issue 3|33
Figure 3: Comparative in vitro drug release
through dialysis membrane
Figure 4: Comparative ex vivo drug release
through porcine ear skin
in vitro / ex vivo drug release from lipogel and
conventional gel
in vitro / ex vivo drug release studies were
performed using Franz diffusion cells having
surface area of 3.91 cm2
and receptor
compartment having a capacity of 22 ml.
Phosphate buffer pH 5.4 was used as receptor
fluid. The pH of the buffer approaches the natural
pH value of human skin.
in vitro: Dialysis membrane filters (molecular
weight cut off 12 000 to 14 000) which were pre-
hydrated by soaking in buffer overnight were
mounted on the cells. Receptor compartment was
filled with buffer as diffusion medium (37±0.5°).
Reservoir solution was stirred at 300 r/min using
magnetic bead. 0.5 g gel was placed in the
donor compartment on the membrane. Aliquots
were collected at 1, 2, 3, 4, 5, 6, 7, 8 &
24 h intervals and analyzed by UV-
spectrophotometry (Figure 3).
ex vivo: Porcine ear skin was shaved and carefully
separated. Subcutaneous fat was removed using
a scalpel. Skin sections were soaked in buffer
overnight. Skin sections thus obtained were
mounted on Franz Diffusion cells. Epidermal side
of the skin was exposed to ambient condition
while dermal side was kept facing the receptor
solution. Receptor compartment was filled with
buffer as diffusion medium (37±0.5°). Reservoir
solution was stirred at 300 r/min using magnetic
bead. 0.5 g gel was placed in the donor
compartment on the skin. All bubbles were
carefully removed between the underside of the
skin and solution in the receiver compartment.
Aliquots were collected at 1, 2, 3, 4, 5, 6, 7, 8 &
24 h intervals and analyzed by UV-
spectrophotometry (Figure 4).
Kinetic modeling
The release data was analysed using zero order,
first order, Higuchi, Hixson-Crowell and
Korsmeyer-Peppas models, to evaluate the
mechanism of drug release from the liposomal
gel. Mathematical models aid in predicting the
drug release rate and diffusion behaviour, thus
reducing the number of experiments needed. It
also helps in understanding the physics of a
particular drug transport phenomenon, thus
enabling the development of new formulations
[14,15] .
Figure 5: Pharmacokinetic release profile
of lipogel (ex vivo)
Anti-elastase assay
Elastase is the only enzyme that is capable of
breaking down elastin, an insoluble elastic fibrous
protein that, together with collagen, determines
the mechanical properties of connective tissue.
Several studies have demonstrated that both skin-
aging and anti-wrinkle effects are significantly
correlated with decreased elastase activity [16].
Therefore anti-elastase assay was carried out of
Rutin trihydrate liposomal gel to confirm its utility
as an anti-wrinkle product. Porcine pancreatic
elastase enzyme was incubated with the sample in
the cuvette. The amount of enzyme left
uninhibited was detected by reacting it with
substrate N-Succ-Ala-Nitroanilide that gives p-
nitroaniline as the final product. This was read
spectrophotometrically at 405 nm. Higher the
amount of product formed, lower is the inhibitory
effect of the sample on the enzyme.
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34 | International Journal of Pharmaceutical Research | July – Sept 2015 | Vol 7 | Issue 3
% Elastase inhibition = (Absorbance of
control –Absorbance of test) x 100
Absorbance of control
Figure 6: Anti‐elastase inhibition by Rutin
trihydrate
V. Skin Irritation Studies
Healthy male albino Wistar rats (Rattus norvegicus
sp.), 180-220 g, 3 months old were selected as
test models. Six animals were used for the study,
each animal served as its own control. The
research project protocol was approved by Local
Institutional Animal Ethics Committee (Approval
No. CPCSEA/IAEC/BNCP/P-10/2014).
All the animals were allowed to acclimatize to
laboratory conditions prior to study. Hair was
removed from the back side of rats and an area
of 1 cm2
was marked on both the sides. One side
served as control while the other as test. Control
and test formulations (200 mg/rat) were applied
on each side and the site was covered with cotton
bandage. Observations for sensitivity and
reaction were made and graded as follows
Grade 1: No reaction, Grade 2: Slight, patchy
erythema, Grade 3: Slight but confluent or
moderate but patchy erythema, Grade 4:
Moderate erythema, Grade 5: Severe erythema.
RESULTS AND DISCUSSION
Method of preparation of liposomes
Thin film hydration method was selected for
preparation of multilamellar liposomes. The
reason behind the selection of thin film hydration
method was that Rutin trihydrate is lipophilic in
nature and has low aqueous solubility, so
multilamellar vesicles are more capable of
loading a higher mass of a hydrophobic drug
than are unilamellar vesicles. Thin film hydration
method was found to give excellent drug loading
with efficiency over 80%. Hence, this method was
used for preparation of liposomes.
Optimization of process parameters
a. Speed of rotation
Uneven film was observed at higher speed of
rotation (150 r/min) during film formation. This
may be due to improper distribution of heat at
higher speed. During film formation, lower speed
increases the time of contact of the film with the
hot water in the water bath. At higher speed,
since sufficient time is not available for the lipid to
form film, liquid to gel transitions of the lipid does
not occur. Based upon these observations 80
r/min was considered optimum for formation of
uniform film.
But, during hydration of lipid film sufficient energy
and vigorous shaking is required for the dried
film to get hydrated and form liposomes, thus
100-150 r/min was found adequate to form
uniform liposomal dispersion.
b. The ratio and volume of solvent blend
The choice of solvent is usually chloroform owing
to its low boiling point (61.15°) and easy removal
under vacuum leading to thin film deposition on
the walls of the flask. Rutin trihydrate is insoluble
in chloroform but soluble in methanol (Boiling
point 64.7°) and thus methanol was used in
combination with chloroform. Chloroform:
methanol in a 2:1 ratio was selected. This ratio
gave an even, uniform film. When the volume of
solvents is low (5 ml or less), solvents evaporate
rapidly under vacuum leading to improper film
formation. On the other hand when the volume
of solvent is high (10 ml or more), inadequate
film drying was observed. The presence of
organic solvent often leads to emulsion
formation. Volume of the solvent system used was
7.5 ml (5 ml Chloroform and 2.5 ml methanol).
c. Quantity of glass beads
Optimum quantity of glass beads is required to
obtain a thin uniform film on the surface of RBF. It
was observed that in the absence of glass beads,
the organic solvents evaporated rapidly even
under slow application of vacuum which lead to
poor film deposition on the walls of RBF, whereas
excessive bead quantity resulted in attrition and
inability of the solvents to evaporate. Glass beads
to solvent ratio 3:1 was found to be optimum as it
gave thin uniform film with no visible aggregates.
22 to 25 g glass beads were found to be
optimum for homogeneous film formation.
d. Vesicle sizing technique
Thin film hydration method gives large,
heterogeneous multilamellar vesicles. Vesicle size
analysis revealed Z-average (d-nm) size of 1360
nm with high PDI of 0.98, but good entrapment
efficiency was achieved. Techniques such as Ultra
Turrax and high pressure homogenization (HPH)
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International Journal of Pharmaceutical Research | July – Sept 2015 | Vol 7 | Issue 3|35
were tried to obtain size reduction and narrow
size distribution i.e. lower PDI. The results
indicated satisfactory size reduction and low PDI
but affected the entrapment efficiency adversely
which could be due to vesicle rupturing at high
pressure and speed. Hence, bath sonication was
used for further batches which gave vesicles in the
size range of 100-500 nm with PDI of 0.6 without
loss in drug entrapment.
e. pH of the hydrating media
According to Handerson Hasselbalch equation,
pKa is defined as the extent to which a drug is
available in the ionized form at a given pH.
pH = pKa + log (ionized/unionised)
Hence, the extent of ionization is influenced by
the pKa of any drug. Thus, entrapment of any
drug depends on its pKa to a considerable extent.
The pKa of Rutin trihydrate is cited as 6.4 in the
literature. Maximum ionization (~90%) would
hence occur at pH values ± one unit of the pKa
value. Phosphate buffer pH 5.4 was selected as it
yielded uniform suspension with minimal
sedimentation and maximum entrapment
efficiency. Sedimentation was observed when pH
of the buffer was raised beyond 7 whereas phase
separation was observed towards acidic pH.
Hence, further batches were prepared at pH value
of 5.4.
Formula optimization
a. Lipid concentration was gradually increased
from 0.5 to 2%. Increase in concentration of lipid
phase leads to increase in viscosity and thus the
settling rate was decreased. Liposomal
suspension with 0.5% lipid was a thin suspension
which exhibited faster settling rate. After 24 h, the
sediment formed took time to redisperse.
Formulation containing 2% lipid was much thicker
and showed less settling even after 24 h. But the
microscopic evaluation showed presence of larger
vesicles and aggregates. In comparison 1% lipid
suspension was found to give satisfactory results
in terms of settling, redispersion and microscopic
observation (Table 1).
b. Drug to lipid ratio was changed from 1:10,
2:10 and 3:10. The molecular weight of Rutin
trihydrate is high (664.56). This factor is of
importance as the amount of drug that enters the
lipid bilayer is also governed by its molecular
weight. The bilayer can only incorporate certain
amount of drug after which the drug starts
sedimenting immediately upon formation.
Microscopic observation also confirms this fact as
the unentrapped drug is clearly visible outside
vesicles. The threshold for Rutin trihydrate was
found to be 1 part of drug per 10 parts of lipid
employed. Hence, 1:10 drug to lipid ratio (10 mg
drug in 100 mg lipid) was found to be optimum
as maximum entrapment efficiency was obtained
by this ratio and optical microscopy showed
minimal unentrapped drug.
c. Phospahatidylcholine: Cholesterol ratio: In
principle, liposomes can be prepared using only
phosphatidylcholine. However, cholesterol is
added to improve stability and other structural
properties. Cholesterol has the effect of making
the membrane less permeable by filling up holes
or disruptions. Liposomes formed only with
phosphatidylcholine gives porous membranes
resulting in drug leakage whereas cholesterol acts
a cementing material thus improving drug
loading capacity of vesicles. Highest entrapment
was obtained with the batches having
Phosphatidylcholine: Cholesterol ratio as 1:0.2.
This could be because, the addition of cholesterol
in this ratio provides optimum rigidity to the
bilayer. Increase in the quantity of cholesterol
causes decrease in entrapment. This can be
explained by the fact that cholesterol might be
replacing Rutin trihydrate in the bilayer (Table 2).
Vesicle Size and Zeta Potential Measurement
MLV’s of size 0.5 to 1 μm were visualized easily
for all the batches using optical microscope (Motic
microscope) at magnification of 100x. TEM
imaging of optimized formulation showed drug
loaded liposomes of somewhat spherical shape.
Vesicles showed inner dark spherical core,
surrounded by comparatively faint background.
Vesicle size of optimized batch was approximately
600 nm (Figure 2).
The zeta potential was used as an indicator of the
stability of vesicles formed by thin film hydration
method. The zeta potential of the optimized batch
was -30.7 which indicates sufficient stability.
Liposomal gels
Liposomal suspensions were converted to gel
formulations since simple mixing of liposomal
dispersions with polymers gives the corresponding
gels. This is advantageous because the fusion of
vesicles can be effectively minimized or avoided
as the polymer molecules serve as a spacer
between the liposomes. Moreover, the size of the
vesicles is not affected because it is a controlled
liposome/polymer interaction process. Liposomal
creams were not chosen as stability problems are
reported in emulsion-based products due to
presence of excess oil and surfactant which may
interact with the vesicles. Various properties like
viscosity can be easily controlled by varying the
amount and type of polymer. Thus liposomal gels
were formulated as they circumvent the stability
issue, provide controlled release, have aesthetic
appeal as skin care cosmetics and are easy to
prepare [15].
Lipogels were pale yellow (colour of Rutin
trihydrate) and opaque. 1% w/w Carbopol gel
8. Aparajita Varshneya et al /Formulation and Characterization of Rutin Liposomes
36 | International Journal of Pharmaceutical Research | July – Sept 2015 | Vol 7 | Issue 3
was found to be of good consistency and
acceptable feel with smooth appearance devoid
of any aggregation. Drug content for the gels
was found to be in the range of 97% to 101%.
Viscosity of gels was in the range of 8500 cps to
9500 cps. Spreadability of gels was around 5-7
g.cm/s.
in vitro / ex vivo drug release
The stratum corneum is built like a wall with
protein bricks and lipid mortar. The intercellular
lipids are important in controlling the
percutaneous absorption. In the case of
liposomes, the phospholipids may mix with the
intercellular lipids and thereby cause the swelling
of lipids without altering the multiple bilayer
structure of the stratum corneum. These swollen
lipids cause accumulation of the drug and thereby
form an intracutaneous depot. Although the
mechanism of enhancement using topically
applied liposomes is not fully understood, drug
disposition is primarily dependent on lipid
composition, liposome lamellarity and surface
charge. Studies have indicated topical drug
delivery is also influenced by the size of liposomes
[17,18].
in vitro and ex vivo application of the liposomal
gel formulation showed sustained release effect.
The drug release was sustained upto 12 hrs in
comparison to 5-6 hrs of conventional gel (Figure
3, Figure 4). This could be due to depot effect of
large multilamellar vesicles. ex vivo drug release
profile of lipogel showed that it follows zero order
kinetics as its R2
value was closest to unity (Figure
5).
Anti-elastase assay
The 0.1 % Rutin trihydrate lipogel showed a mean
anti-elastase activity of 32.01 ± 1.40 % at a
concentration of 3000 μg/ml. 32% inhibition at
0.1% concentration of Rutin trihydrate indicates
good activity of the formulation (Figure 6).
Skin Irritation Study
Skin irritation study conducted on albino Wistar
rats when observed for sensitivity and reaction at
the end of 24, 48 and 72 h showed absence of
erythema or edema for both the formulations
(control as well as test). This indicates that the gels
do not cause any skin irritation as no sensitivity
reaction (redness/ erythema) was observed.
CONCLUSION
Liposomes have been reported to be efficient
colloidal carriers for the delivery of therapeutics
into skin. This work too confirms the promising
role of liposomal topical formulation.
Multilamellar vesicles with good entrapment
efficiency were successfully prepared by thin film
hydration method and the drug containing
liposomes were formulated into a gel. The
liposomal gel showed prolonged drug release
upto 12 h and also exhibited anti-elastase activity.
Due to the striking similarity between liposome
components and skin lipids, they are safe and
effective. In addition to delivering the drug in
higher concentration into skin layers, they
enhance skin hydration making them an ideal
vehicle for anti-aging remedies. Thus liposomes
can be considered as effective carriers for better
topical delivery.
ACKNOWLEDGEMENTS
The authors are thankful to VAV Life Sciences Pvt.
Ltd., Mumbai for gift sample of Leciva-S70
(soya lecithin). They also sincerely thank NIRRH,
Mumbai for TEM imaging, Dr. Kshitij Vasant,
Kelkar College, Mumbai for anti-elastase assay
and NMIMS’s SPTM College, Mumbai for helping
in carrying out skin irritation studies.
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