Niosomes are a novel drug delivery system composed of a bilayer of non-ionic surfactants encapsulating medications. They offer advantages over liposomes including improved stability and flexibility in structural characteristics. Niosomes can be prepared through various methods like film hydration, ether injection, sonication, and microfluidization. Key factors affecting their formation include the surfactant, cholesterol level, drug properties, and preparation technique used. Niosomes can improve drug bioavailability, target delivery to sites of action, and provide protection from degradation, making them a promising drug carrier system.
‘Targeted drug delivery system is a special form of drug delivery system where the medicament is selectively targeted or delivered only to its site of action or absorption and not to the non-target organs or tissues or cells.’
Gastro retentive drug delivery system (GRDDS)Shweta Nehate
Oral route is the most acceptable route for drug administration. Apart from conventional dosage forms several other forms were developed in order to enhance the drug delivery for prolonged time period and for delivering drug to a particular target site. Gastro-retentive drug delivery system (GRDDS) has gainned immense popularity in the field of oral drug delivery recently. it is a widely employed approach to retain the dosage form in the stomach for an extended period of time and release the drug slowly that can address many challenges associated with conventional oral delivery, including poor bioavailability. different innovative approaches are being applied to fabricate GRDDS. Gastroretentive drug delivery is an approach to prolong gastric residence time, there by targeting site-specific drugs release in the upper gastrointestinal tract (GIT) for local or systemic effects. It is obtained by retaining dosage form into stomach and by releasing the in controlled manner.
NIOSOMES , GENERAL CHARACTERISTICS OF NIOSOME , TYPES OF NIOSOMES , OTHERS TYPES OF NIOSOMES , NIOSOMES VS LIPOSOMES , COMPONENTS OF NIOSOMES , Non-ionic surfactant , Cholesterol , Charge inducing molecule , METHOD OF PREPARATION , preparation of small unilamellar vesicles , Sonication , Micro fluidization , preparation of large unilamellar vesicles , Reverse Phase Evaporation , Ether Injection , preparation of Multilamellar vesicles , Hand shaking method , Trans membrane pH gradient drug uptake process (remote loading) , Miscellaneous method :Multiple membrane extrusion method , The “Bubble” Method , Formation of Niosomes From Proniosomes , SEPARATION OF UNENTRAPPED DRUGS , Gel Filtration , Dialysis , Centrifugation , FACTORS AFFECTING THE PHYSICOCHEMICAL PROPERTIES OF NIOSOMES , Membrane Additives , Temperature of Hydration , PROPERTIES OF DRUGS , AMOUNT AND TYPE OF SURFACTANT
Structure of Surfactants , Resistance to Osmotic Stress , Characterization of niosomes ,Therapeutic applications of Niosomes , For Controlled Release of Drugs , To Improve the Stability and Physical Properties of the Drugs , For Targeting and Retention of Drug in Blood Circulation , Proniosomes , Aspasomes , Vesicles in Water and Oil System (v/w/o) ,Bola - niosomes , Discomes , Deformable niosomes or elastic niosomes , According to the nature of lamellarity ,Small Unilamellar vesicles (SUV) 25 – 500 nm in size.,Large Unilamellar vesicles (LUV) 0.1 – 1μm in size , Multilamellar vesicles (MLV) 1-5 μm in size , According to the size:Small Niosomes (100 nm – 200 nm) , Large Niosomes (800 nm – 900 nm),Big Niosomes (2 μm – 4 μm)
Introduction
Structure
Niosomes Vs. Liposome
Advantages & Disadvantages
Properties of Niosomes
Method of Manufacturing
Evaluation of Niosomes
Applications
Marketed products
Mucoadhesive drug delivery system interact with the mucus layer covering the mucosal epithelial surface, & mucin molecules & increase the residence time of the dosage form at the site of the absorption.
Mucoadhesive drug delivery system is a part of controlled delivery system.
Since the early 1980,the concept of Mucoadhesion has gained considerable interest in pharmaceutical technology.
combine mucoadhesive with enzyme inhibitory & penetration enhancer properties & improve the patient complaince.
MDDS have been devloped for buccal ,nasal,rectal &vaginal routes for both systemic & local effects.
Hydrophilic high mol. wt. such as peptides that cannot be administered & poor absorption ,then MDDS is best choice.
Mucoadhesiveinner layers called mucosa inner epithelial cell lining is covered with viscoelasticfluid
Composed of water and mucin.
Thickness varies from 40 μm to 300 μm
General composition of mucus
Water…………………………………..95%
Glycoproteinsand lipids……………..0.5-5%
Mineral salts……………………………1%
Free proteins…………………………..0.5-1%
The mechanism responsible in the formation of mucoadhesive bond
Step 1 : Wetting and swelling of the polymer(contact stage)
Step 2 : Interpenetration between the polymer chains and the mucosal membrane
Step 3 : Formation of bonds between the entangled chains (both known as consolidation stage)
Electronic theory
Wetting theory
Adsorption theory
Diffusion theory
Fracture theory
Advantages over other controlled oral controlled release systems by virtue of prolongation of residence of drug in GIT.
Targeting & localization of the dosage form at a specific site
-Painless administration.
-Low enzymatic activity & avoid of first pass metabolism
If MDDS are adhere too tightlgy because it is undesirable to exert too much force to remove the formulation after use,otherwise the mucosa could be injured.
-Some patient suffers unpleasent feeling.
-Unfortunately ,the lack of standardized techniques often leads to unclear results.
-costly drug delivery system
‘Targeted drug delivery system is a special form of drug delivery system where the medicament is selectively targeted or delivered only to its site of action or absorption and not to the non-target organs or tissues or cells.’
Gastro retentive drug delivery system (GRDDS)Shweta Nehate
Oral route is the most acceptable route for drug administration. Apart from conventional dosage forms several other forms were developed in order to enhance the drug delivery for prolonged time period and for delivering drug to a particular target site. Gastro-retentive drug delivery system (GRDDS) has gainned immense popularity in the field of oral drug delivery recently. it is a widely employed approach to retain the dosage form in the stomach for an extended period of time and release the drug slowly that can address many challenges associated with conventional oral delivery, including poor bioavailability. different innovative approaches are being applied to fabricate GRDDS. Gastroretentive drug delivery is an approach to prolong gastric residence time, there by targeting site-specific drugs release in the upper gastrointestinal tract (GIT) for local or systemic effects. It is obtained by retaining dosage form into stomach and by releasing the in controlled manner.
NIOSOMES , GENERAL CHARACTERISTICS OF NIOSOME , TYPES OF NIOSOMES , OTHERS TYPES OF NIOSOMES , NIOSOMES VS LIPOSOMES , COMPONENTS OF NIOSOMES , Non-ionic surfactant , Cholesterol , Charge inducing molecule , METHOD OF PREPARATION , preparation of small unilamellar vesicles , Sonication , Micro fluidization , preparation of large unilamellar vesicles , Reverse Phase Evaporation , Ether Injection , preparation of Multilamellar vesicles , Hand shaking method , Trans membrane pH gradient drug uptake process (remote loading) , Miscellaneous method :Multiple membrane extrusion method , The “Bubble” Method , Formation of Niosomes From Proniosomes , SEPARATION OF UNENTRAPPED DRUGS , Gel Filtration , Dialysis , Centrifugation , FACTORS AFFECTING THE PHYSICOCHEMICAL PROPERTIES OF NIOSOMES , Membrane Additives , Temperature of Hydration , PROPERTIES OF DRUGS , AMOUNT AND TYPE OF SURFACTANT
Structure of Surfactants , Resistance to Osmotic Stress , Characterization of niosomes ,Therapeutic applications of Niosomes , For Controlled Release of Drugs , To Improve the Stability and Physical Properties of the Drugs , For Targeting and Retention of Drug in Blood Circulation , Proniosomes , Aspasomes , Vesicles in Water and Oil System (v/w/o) ,Bola - niosomes , Discomes , Deformable niosomes or elastic niosomes , According to the nature of lamellarity ,Small Unilamellar vesicles (SUV) 25 – 500 nm in size.,Large Unilamellar vesicles (LUV) 0.1 – 1μm in size , Multilamellar vesicles (MLV) 1-5 μm in size , According to the size:Small Niosomes (100 nm – 200 nm) , Large Niosomes (800 nm – 900 nm),Big Niosomes (2 μm – 4 μm)
Introduction
Structure
Niosomes Vs. Liposome
Advantages & Disadvantages
Properties of Niosomes
Method of Manufacturing
Evaluation of Niosomes
Applications
Marketed products
Mucoadhesive drug delivery system interact with the mucus layer covering the mucosal epithelial surface, & mucin molecules & increase the residence time of the dosage form at the site of the absorption.
Mucoadhesive drug delivery system is a part of controlled delivery system.
Since the early 1980,the concept of Mucoadhesion has gained considerable interest in pharmaceutical technology.
combine mucoadhesive with enzyme inhibitory & penetration enhancer properties & improve the patient complaince.
MDDS have been devloped for buccal ,nasal,rectal &vaginal routes for both systemic & local effects.
Hydrophilic high mol. wt. such as peptides that cannot be administered & poor absorption ,then MDDS is best choice.
Mucoadhesiveinner layers called mucosa inner epithelial cell lining is covered with viscoelasticfluid
Composed of water and mucin.
Thickness varies from 40 μm to 300 μm
General composition of mucus
Water…………………………………..95%
Glycoproteinsand lipids……………..0.5-5%
Mineral salts……………………………1%
Free proteins…………………………..0.5-1%
The mechanism responsible in the formation of mucoadhesive bond
Step 1 : Wetting and swelling of the polymer(contact stage)
Step 2 : Interpenetration between the polymer chains and the mucosal membrane
Step 3 : Formation of bonds between the entangled chains (both known as consolidation stage)
Electronic theory
Wetting theory
Adsorption theory
Diffusion theory
Fracture theory
Advantages over other controlled oral controlled release systems by virtue of prolongation of residence of drug in GIT.
Targeting & localization of the dosage form at a specific site
-Painless administration.
-Low enzymatic activity & avoid of first pass metabolism
If MDDS are adhere too tightlgy because it is undesirable to exert too much force to remove the formulation after use,otherwise the mucosa could be injured.
-Some patient suffers unpleasent feeling.
-Unfortunately ,the lack of standardized techniques often leads to unclear results.
-costly drug delivery system
Video Lecture is available at https://www.youtube.com/watch?v=DXu_CLgB4q0
Introduction, terminology/definitions and rationale, advantages, disadvantages, selection of drug candidates. Approaches to design-controlled release formulations based on diffusion, dissolution and ion exchange principles. Physicochemical and
biological properties of drugs relevant to controlled release formulations.
Liposomes-Classification, methods of preparation and application Vijay Hemmadi
liposome preparation and application
A liposome is a tiny bubble (vesicle), made out of the same material as a cell membrane. Liposomes can be filled with drugs, and used to deliver drugs for cancer and other diseases. Membranes are usually made of phospholipids, which are molecules that have a head group and a tail group
Liposomes, Structure of liposome, phospholipids, classification of liposomes, method of preparation of liposomes, mechanism of liposome formation, application of liposomes.
Video Lecture is available at https://www.youtube.com/watch?v=DXu_CLgB4q0
Introduction, terminology/definitions and rationale, advantages, disadvantages, selection of drug candidates. Approaches to design-controlled release formulations based on diffusion, dissolution and ion exchange principles. Physicochemical and
biological properties of drugs relevant to controlled release formulations.
Liposomes-Classification, methods of preparation and application Vijay Hemmadi
liposome preparation and application
A liposome is a tiny bubble (vesicle), made out of the same material as a cell membrane. Liposomes can be filled with drugs, and used to deliver drugs for cancer and other diseases. Membranes are usually made of phospholipids, which are molecules that have a head group and a tail group
Liposomes, Structure of liposome, phospholipids, classification of liposomes, method of preparation of liposomes, mechanism of liposome formation, application of liposomes.
Niosomes are vesicles composed mainly of hydrated non-ionic surfactant with or without cholesterol used for targetted drug delivery. Niosomes are better than liposomes as they are cost effective, stable, and can be stored for a long period of time.
Liposomes are concentric bilayered vesicles in which an aqueous core is entirely enclosed by a membranous lipid bilayer mainly composed of natural or synthetic phospholipids.
Liposomes are spherical microscopic vesicles consisting phospholipids bilayers which enclose aqueous compartments.
The size of a liposome ranges from some 20 nm up to several micrometers.
Liposomes were first produced in England in 1961 by Alec D. Bangham, who was studying phospholipids and blood clotting.
Small unilamellar vesicles (SUV), 25 to 100 nm in size that consist of a single bilayer
Large unilamellar vesicle (LUV), 100 to 500 nm in size that consist of a single bilayer
Multilamellar vesicle (MLV), 200 nm to several microns, that consist of two or more concentric bilayer
ABSTRACT
The parenteral administration route is the most effective and common form of delivery for active drug substances with poor bioavailability and the drugs with a narrow therapeutic index. Drug delivery technology that can reduce the total number of injection throughout the drug therapy period will be truly advantageous not only in terms of compliance, but also to improve the quality of the therapy and also may reduce the dosage frequency. Such reduction in frequency of drug dosing is achieved by the use of specific formulation technologies that guarantee the release of the active drug substance in a slow and predictable manner. The development of new injectable drug delivery system has received considerable attention over the past few years. A number of technological advances have been made in the area of parenteral drug delivery leading to the development of sophisticated systems that allow drug targeting and the sustained or controlled release of parenteral medicines.
Niosomes is under the Novel drug delivery system. In which the drug are enclosed in the bilayer vesicle which is made up of the phospholipid. Niosomes are the similar to the liposomes both are made up of the bilayer of phospholipid. But in niosomes several advantages of over the liposomes.
A PHARMACEUTICAL NANOSUSPENSION IS DEFINED AS: “Very finely dispers solid drug particles in an aqueous vehicale for either oral and topical use or parenteral and pulmonary administration.
liposomes and nanoparticles drug delivery systemShreyaBhatt23
this presentation includes the intro duction to targeted drug delivery systems using nanoparticulate systems like liposomes, nanoparticles, mechanism of action, types, preparation, advantages, applications
Nanoemulsion Characterisation Techniques and Formulation Methodsijtsrd
Nanoemulsions are thermodynamically stable colloidal dispersion systems made up of two immiscible liquids combined with emulsifying agents surfactants and co surfactants to produce a single phase. Nanoemulsions have been studied extensively as drug delivery devices. This review attempts to bring together information on the many nanoemulsion formulation and characterization techniques that have been developed. The persuasion approach and the Brute force method are two methods for creating nanoemulsions. Entrapment efficiency, particle size, polydispersity index, zeta potential, and characterization using differential scanning calorimetry, Fourier transform infrared spectroscopy, and transmission electron microscopy are just a few of the techniques used to characterise nanoemulsions. In vitro drug release, in vitro permeation, stability and thermodynamic stability, shelf life, dispersibility, viscosity, surface tension, friccohesity, refractive index, transmittance, pH, and osmolarity are all used to assess nanoemulsions. Rohit Ghogare | Prof. Santosh Waghmare | Dr. Hemant Kamble "Nanoemulsion- Characterisation Techniques and Formulation Methods" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-3 , April 2022, URL: https://www.ijtsrd.com/papers/ijtsrd49586.pdf Paper URL: https://www.ijtsrd.com/pharmacy/other/49586/nanoemulsion-characterisation-techniques-and-formulation-methods/rohit-ghogare
Biosafety is the prevention of large-scale loss of biological integrity, focusing both on ecology and human health. These prevention mechanisms include conduction of regular reviews of the biosafety in laboratory settings, as well as strict guidelines to follow. Biosafety also means safety from exposure to infectious agents.
Necessity
In order to avoid infection/biohazard to the laboratory personnel & the environment, biosafety levels are very important.
Medical writing is the activity of writing scientific documentation by someone who is a specialized writer (a medical writer) and is generally not one of the scientists or doctors whose research it was..
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
- 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
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
Muktapishti is a traditional Ayurvedic preparation made from Shoditha Mukta (Purified Pearl), is believed to help regulate thyroid function and reduce symptoms of hyperthyroidism due to its cooling and balancing properties. Clinical evidence on its efficacy remains limited, necessitating further research to validate its therapeutic benefits.
Basavarajeeyam is an important text for ayurvedic physician belonging to andhra pradehs. It is a popular compendium in various parts of our country as well as in andhra pradesh. The content of the text was presented in sanskrit and telugu language (Bilingual). One of the most famous book in ayurvedic pharmaceutics and therapeutics. This book contains 25 chapters called as prakaranas. Many rasaoushadis were explained, pioneer of dhatu druti, nadi pareeksha, mutra pareeksha etc. Belongs to the period of 15-16 century. New diseases like upadamsha, phiranga rogas are explained.
Best Ayurvedic medicine for Gas and IndigestionSwastikAyurveda
Here is the updated list of Top Best Ayurvedic medicine for Gas and Indigestion and those are Gas-O-Go Syp for Dyspepsia | Lavizyme Syrup for Acidity | Yumzyme Hepatoprotective Capsules etc
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
Title: Sense of Smell
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 primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
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.
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
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.
Adv. biopharm. APPLICATION OF PHARMACOKINETICS : TARGETED DRUG DELIVERY SYSTEMSAkankshaAshtankar
MIP 201T & MPH 202T
ADVANCED BIOPHARMACEUTICS & PHARMACOKINETICS : UNIT 5
APPLICATION OF PHARMACOKINETICS : TARGETED DRUG DELIVERY SYSTEMS By - AKANKSHA ASHTANKAR
Triangles of Neck and Clinical Correlation by Dr. RIG.pptx
Niosomes - A novel drug delivery system
1. NIOSOMES: A NOVEL DRUG
DELIVERY SYSTEM
Presented by:
Anirban Saha
M.Pharm (Pharmaceutics)
Amity Institute of Pharmacy (AIP)
AMITY INSTITUTE OF
PHARMACY
2. Introduction
Factors Affecting Niosomes Preparation
Methods of Preparation
Characterization of Niosomes
Stability of Niosomes
Applications of Niosomes
Toxicity of Niosomes
PRESENTATION FLOW
3. NOVEL DRUG DELIVERY SYSTEM (NDDS)
Refers to approaches, formulations, technologies, and
systems for transporting a pharmaceutical compound in the
body as needed to safely achieve its desired therapeutic
effect
May involve scientific site-targeting within the body, or
facilitating systemic pharmacokinetics
Technologies modify drug release profile, absorption,
distribution and elimination for the benefit of
Improving product efficacy and safety
Patient convenience and compliance
INTRODUCTION
4. EXAMPLES OF NDDS
• Niosomes
• Liposomes
• Nanoparticles
• Resealed erythrocytes
• Microspheres
• Monoclonal antibodies
• Micro emulsions
• Antibody-loaded drug
delivery
• Magnetic microcapsules
• Implantable pumps
Figure 1: various drug delivery systems (Aitha S, 2013)
5. Novel drug delivery system, in
which the medication is
encapsulated in a vesicle which is
composed of a bilayer of non-ionic
surface active agents (Nasir A, 2012)
Are very small, and microscopic in
size.
Although structurally similar to
liposomes, they offer several
advantages over them.
NIOSOMES
Figure 2: Niosomes Vesicles (Aitha S, 2013)
6. The vesicles forming
amphiphile is a non-ionic
surfactant stabilized by
addition of cholesterol and
small amount of anionic
surfactant such as dicetyl
phosphate
NIOSOMES
Figure 3: Vesicle of niosome (Aitha S, 2013)
7. Figure 4: Structure of Niosomes
STRUCTURE
OF NIOSOMES
similar to liposomes, in that they are also
made up of a bilayer.
However, the bilayer in the case of
Niosomes is made up of non-ionic
surface active agents rather than
phospholipids.
Made of a surfactant bilayer with its
hydrophilic ends exposed on the outside
and inside of the vesicle, while the
hydrophobic chains face each other
within the bilayer.
(Patel SM et al, 2012)
(Makeshwar KB, 2013)
8. STRUCTURE
OF NIOSOMES
vesicle holds hydrophilic
drugs within the space
enclosed in the vesicle,
while hydrophobic drugs
are embedded within the
bilayer itself.
Niosomes vesicle would
consist of a vesicle
forming amphiphile i.e. a
non-ionic surfactant such
as Span- 60, which is
usually stabilized by the
addition of cholesterol
(Makeshwar KB, 2013)
Figure 5: Structure of niosome (Makeshwar KB, 2013)
9. Entrap solutes in a manner analogous to liposomes.
Osmotically active and stable.
Accommodate the drug molecules with a wide range of
solubility.
Exhibits flexibility in their structural characteristics
(composition, fluidity and size)
Performance of the drug molecules is increased.
Better availability to the particular site by protecting the
drug from biological environment.
Surfactants used in preparation are biodegradable,
biocompatible and non-immunogenic
SALIENT FEATURES OF
NIOSOMES (Makeshwar KB, 2013)
10. Improve the therapeutic performance of the drug molecules by
Delayed clearance from the circulation
Protecting the drug from biological environment
Restricting effects to target cells
Niosomal dispersion in an aqueous phase can be emulsified in a
nonaqueous phase to
Regulate the delivery rate of drug
Administer normal vesicle in external non-aqueous phase.
Handling and storage of surfactants requires no special conditions.
Bioavailability of poorly absorbed drugs is increased.
Targeted to the site of action by oral, parenteral as well as topical
routes.
ADVANTAGES OF NIOSOMES
DELIVERY SYSTEM(Makeshwar KB, 2013)
11. According to the nature of lamellarity
1. Multilamellar vesicles (MLV) 1-5 μm in size.
2. Large Unilamellar vesicles (LUV) 0.1 – 1μm in size
3. Small Unilamellar vesicles (SUV) 25 – 500 nm in size.
According to the size
1. Small Niosomes (100 nm – 200 nm)
2. Large Niosomes (800 nm – 900 nm)
3. Big Niosomes (2 μm – 4 μm)
TYPES OF NIOSOMES
13. Type of surfactant influences encapsulation efficiency,
toxicity, and stability of Niosomes
NATURE OF SURFACTANT
14. The surfactant/lipid ratio is generally 10-30 mM (1-2.5%
w/w)
Increasing the surfactant/lipid level increases the total
amount of drug encapsulated
SURFACTANT AND LIPID LEVELS
15. NATURE OF THE DRUG
The Physio-chemical properties
of encapsulated drug influence
charge and rigidity of the
Niosome bilayer.
The drug interacts with
surfactant head groups and
develops the charge that creates
mutual repulsion between
surfactant bilayers, and hence
increases vesicle size.
The aggregation of vesicles is
prevented due to the charge
development on bilayer.
Effect of the nature of drug on
formation vesicle
16. CHOLESTEROL(Tamizharas S et al, 2009)
Addition of cholesterol molecule to
Niosomal system
• Makes the membrane rigid
• Reduces leakage of drug from the Niosome
• Increases the chain order of bilayer
• Strengthen the non-polar tail of the non-ionic
surfactant
• Increase in the entrapment efficiency
• Leads to the transition from the gel state to
liquid phase in Niosomes systems
MEMBRANE ADDITIVES
Cholesterol
17. Charge inducers are one of the membrane
additives which are often included in Niosomes
because
Increase surface charge density
Prevent vesicles flocculation, Aggregation and
Fusion.
Examples: Dicetyl phosphate (DCP) and Stearyl
amine (SA)
MEMBRANE ADDITIVES
(Nasir A, 2012)
18. Film Method
Ether Injection Method
Sonication
Reverse Phase Evaporation
Heating Method
Microfluidization
Multiple Membrane Extrusion Method
Transmembrane pH gradient (inside acidic) Drug
Uptake Process (remote Loading)
The “Bubble” Method
Formation of Niosomes from Proniosomes
METHODS OF PREPARATION
(Madhav NVS, 2011)
19. •Mixture of
Surfactant and
Cholesterol
Dissolved in an
organic solvent
in a round-
bottomed flask.
(e.g. diethyl
ether,
chloroform, etc.)
•organic solvent is
removed by low
pressure/vacuum at
room temperature
example
using a
rotary
evaporator.
• The resultant
dry surfactant
film is hydrated
by agitation at
50–60°C
Multilamellar
vesicles
(MLV) are
formed
FILM METHOD
• Also known as hand shaking method
21. A solution of the surfactant is
made by dissolving it in diethyl
ether.
This solution is then introduced using an
injection (14 gauge needle) into warm water
or aqueous media containing the drug
maintained at 60°C.
Vaporization of the ether
leads to the formation of
single layered vesicles.
• The particle size of the Niosomes formed depend on the
conditions used, and can range anywhere between 50-1000
μm. (Madhav NVS, 2011)
ETHER INJECTION METHOD
Figure 7: Steps of Ether injection method (Madhav NVS, 2011)
22. The mixture is
probe sonicated
at 60°C for 3
minutes using a
sonicator with a
titanium probe to
yield Niosomes.
Added to the
surfactant/
cholesterol
mixture in a
10 ml glass
vial
Aliquot
of drug
solution
in buffer
SONICATION
Figure 8: Sonication method (Madhav NVS, 2011)
23. Creation of a solution
of cholesterol and
surfactant (1:1 ratio)
in a mixture of ether
and chloroform
An aqueous phase
containing the drug
to be loaded is
added to this
Resulting two
phases are
sonicated at 4-
5°C
A clear gel is
formed which is
further sonicated
after the addition
of phosphate
buffered saline
(PBS)
Temperature is
raised to 40°C and
pressure is reduced
to remove the
organic phase
Viscous Niosome
suspension is formed
which can be diluted
with PBS and heated
on a water bath at
60°C for 10 minutes
to yield Niosomes
REVERSE PHASE EVAPORATION
24. Non-toxic, Scalable and one-step method.
HEATING METHOD
Mixtures of non-ionic
surfactant, cholesterol
and/or charge inducing
molecules are added to an
aqueous medium e.g.
buffer, distilled H2O, etc
• In the presence of a
Polyol such as glycerol.
The mixture is
heated while
stirring at low
shear forces
• Until vesicles are
formed
25. Recent technique used to prepare Unilamellar vesicles of
defined size distribution.
based on submerged jet principle
MICROFLUIDIZATION
Two fluidized
streams interact at
ultra high velocities,
in precisely defined
micro channels
within the interaction
chamber
The impingement of thin
liquid sheet along a
common front is arranged
such that the energy
supplied to the system
remains within the area of
Niosomes formation
The result is a greater
uniformity, smaller
size and better
reproducibility of
Niosome are formed
27. Good method for controlling Niosomes size.
MULTIPLE MEMBRANE EXTRUSION
METHOD
Mixture of surfactant, cholesterol and
dicetyl phosphate in chloroform is made
into thin film by evaporation
The film is hydrated with aqueous drug
solution
Resultant suspension is extruded through
polycarbonate membranes which are
placed in series for upto 8 passages
Figure 10: Multiple membrane
extrusion method (Madhav NVS, 2011)
28. Solution of surfactant
and cholesterol is made
in chloroform
Solvent is then evaporated
under reduced pressure to get
a thin film on the wall of the
round bottom flask, similar to
the hand shaking method
This film is then
hydrated using citric acid
solution by vortex
mixing
Resulting Multilamellar
vesicles are then treated
to three freeze thaw
cycles and sonicated
To the Niosomal
suspension, aqueous
solution containing
10mg/ml of drug is
added and vortexed
pH of the sample is
then raised to 7.0-7.2
using 1M disodium
phosphate
Mixture is heated at
60°C for 10 minutes to
give Niosomes
TRANSMEMBRANE pH GRADIENT DRUG
UPTAKE PROCESS
29. A recently developed technique which allows the preparation of
Niosomes without the use of organic solvents.
BUBBLE METHOD
The bubbling unit consists of a round bottom flask with three
necks, and this is positioned in a water bath to control the
temperature.
Water-cooled reflux and thermometer is positioned in the
first and second neck, while the third neck is used to supply
nitrogen.
Cholesterol and surfactant are dispersed together in a buffer
(pH 7.4) at 70°C.
This dispersion is mixed for a period of 15 seconds with
high shear homogenizer and immediately afterwards, it is
bubbled at 70°C using the nitrogen gas to yield Niosomes.
30. FORMATION OF NIOSOMES FROM
PRONIOSOMES (Makeshwar KB, 2013)
Water soluble
carrier such as
sorbitol is
coated with
surfactant.
The result of the
coating process is a
dry formulation in
which each water-
soluble particle is
covered with a thin
film of dry
surfactant.
This preparation
is termed
“Proniosomes”.
The Niosomes
are recognized by
the addition of
aqueous phase at
T > Tm and brief
agitation.
T=Temperature.
Tm = mean phase transition temperature
32. 1) Dialysis:
The aqueous niosomal dispersion is dialyzed in a dialysis tubing
against phosphate buffer or normal saline or glucose solution.
2) Gel Filtration:
The unentrapped drug is removed by gel filtration of niosomal
dispersion through a Sephadex-G -50 column and elution with
phosphate buffered saline or normal saline.
3) Centrifugation:
The niosomal suspension is centrifuged and the supernatant is
separated. The pellet is washed and then resuspended to obtain a
niosomal suspension free from unentrapped drug.
POST-PREPARATION PROCESSES
(Makeshwar KB, 2013)
33. a) Size, Shape and Morphology
b) Entrapment efficiency
c) Vesicle diameter
d) In vitro release
e) Vesicle charge
f) Bilayer rigidity and Homogeneity
g) Osmotic Shrinkage
h) Physical stability of vesicles at different temperature
i) Turbidity Measurement
CHARACTERIZATION OF NIOSOMES
34. Structure of surfactant based vesicles has been visualized
and established using freeze fracture microscopy
Photon correlation spectroscopy used to determine mean
diameter of the vesicles.
Electron microscopy used for morphological studies of
vesicles
Laser beam is generally used to determine size distribution,
mean surface diameter and mass distribution of Niosomes.
SIZE, SHAPE AND MORPHOLOGY
35. After preparing Niosomal dispersion, unentrapped drug is
separated by
Dialysis
Centrifugation
Gel filtration
Drug remained entrapped in Niosomes is determined by
complete vesicle disruption using 50% n-propanol or
0.1% Triton X-100 and analysing the resultant solution by
appropriate assay method for the drug. (Bragagnia M, 2012)
ENTRAPMENT EFFICIENCY
36. To determine drug loading and encapsulation efficiency,
the niosomal aqueous suspension was ultracentrifuged,
supernatant was removed and sediment was washed
twice with distilled water in order to remove the
adsorbed drug.
The Niosomal recovery was calculated as:
NIOSOMAL DRUG LOADING
(Makeshwar KB, 2013)
37. Niosomes diameter can be determined using
Light microscopy
Photon correlation microscopy
Freeze fracture electron microscopy.
Freeze thawing
VESICLE DIAMETER(Shirsand SB, 2012)
Figure 11: Microphotograph of niosomes (Shrisand SB, 2012)
38. At various time intervals, the buffer is analysed for the drug content by an appropriate
assay method.
The bag containing the vesicles is placed in 200 ml of buffer solution in a 250 ml beaker
with constant shaking at 25°C or 37°C.
The vesicle suspension is pipetted into a bag made up of the tubing and sealed.
A dialysis sac is washed and soaked in distilled water.
A method of in-vitro release rate study includes the use of dialysis tubing.
IN VITRO RELEASE(Makeshwar KB, 2013)
39. The vesicle surface charge can play an important role in the
behaviour of Niosomes in vitro and in vivo.
Charged Niosomes are more stable against aggregation and
fusion than uncharged vesicles.
In order to obtain an estimate of the surface potential, the zeta
potential of individual Niosomes can be measured by
Microelectrophoresis, Fluorophores, and Dynamic light
scattering.
Zeta potential is calculated by using Henry equation (S P Vyas, 2011)
ζ =
µ𝐸4πη
Σ
Where ζ is Zeta potential, µ𝐸 is electrophoretic mobility, η is
viscosity of the medium and Σ is dielectric constant
VESICLE CHARGE
(Makeshwar KB, 2013)
40. The biodistribution and biodegradation of Niosomes are
influenced by rigidity of the bilayer.
Homogeneity can occur both within Niosomes structures
themselves and between Niosomes in dispersion and
could be identified via. NMR, Differential Scanning
Calorimetry (DSC) and Fourier transform-infra red
spectroscopy (FT-IR) techniques.
Membrane rigidity can be measured by means of
mobility of fluorescence probe as a function of
temperature. (Patel SM et al, 2012)
BILAYER RIGIDITY AND HOMOGENEITY
41. Osmotic shrinkage of vesicles can be determined by
monitoring reductions in vesicle diameter, initiated by
addition of hypertonic salt solution to suspension of
Niosomes.
Niosomes prepared from pure surfactant are osmotically
more sensitive in contrast to vesicles containing cholesterol.
OSMOTIC SHRINKAGE
42. Aggregation or fusion of vesicles as a function of
temperature was determined as the changes in vesicle
diameter by laser light scattering method.
The vesicles were stored in glass vials at room
temperature or kept in refrigerator (4oC) for 3 months.
The changes in morphology of Multilamellar vesicles
(MLVs) and also the constituent separation were assessed
by an optical microscope.
The retention of entrapped drug were measured 72 hours
after preparation and after 1, 2 or 3 months in same
formulations
PHYSICAL STABILITY OF VESICLES
AT DIFFERENT TEMPERATURE
43. Niosomes were diluted with bidistilled water to give a total
lipid concentration of 0.312 mM
After rapid mixing by sonication for 5 min
Turbidity was measured as the absorbance with an
ultraviolet-visible diode array spectrophotometer.
TURBIDITY MEASUREMENT
44. Vesicles are stabilized based upon formation of 4 different
forces:
1. Van der Waals forces among surfactant molecules
2. Repulsive forces emerging from the electrostatic
interactions among charged groups of surfactant
molecules
3. Entropic repulsive forces of the head groups of
surfactants
4. Short-acting repulsive forces.
STABILITY OF NIOSOMES
46. A surfactant used for preparation of Niosomes must have a
hydrophilic head and hydrophobic tail.
The hydrophobic tail may consist of one or two alkyl or
perfluoroalkyl groups or in some cases a single steroidal
group.
The ether type surfactants with single chain alkyl as
hydrophobic tail is more toxic than corresponding dialkylether
chain.
The ester type surfactants are chemically less stable than ether
type surfactants and the former is less toxic than the latter due
to ester-linked surfactant degraded by esterases to
triglycerides and fatty acid in vivo.
The surfactants with alkyl chain length from C12-C18 are
suitable for preparation of Niosome.
NATURE OF SURFACTANT
(Singh CH, 2011)
47. The geometry of vesicle to be formed from surfactants is affected by its
structure, which is related to critical packing parameters
Critical packing parameters can be defined using following equation,
𝐶𝑝𝑝 =
𝑣
lc
∗ a0
Where
v = hydrophobic group volume,
lc = the critical hydrophobic group length
a0 = the area of hydrophilic head group
From the critical packing parameter value type of miceller structure
formed can be ascertained as given below,
If CPP < ½ then formation of spherical micelles,
If ½ < CPP < 1 formation of bilayer micelles,
If CPP > 1 formation inverted micelles23.
surfactants with longer alkyl chains generally give larger vesicles
STRUCTURE OF SURFACTANT
(Madhav NVS, 2011)
48. The physico-chemical properties of encapsulated drug
influence charge and rigidity of the Niosome bilayer.
The drug interacts with surfactant head groups and
develops the charge that creates mutual repulsion between
surfactant bilayers and hence increases vesicle size.
NATURE OF ENCAPSULATED DRUG
(Singh CH, 2011)
49. Hydration temperature influences the shape and size of
the Niosome.
For ideal condition it should be above the gel to liquid
phase transition temperature of system.
Temperature change of Niosomal system affects
assembly of surfactants into vesicles and also induces
vesicle shape transformation
TEMPERATURE OF HYDRATION
(Madhav NVS, 2011)
50. Niosomes as Drug Carriers
Diagnostic imaging with Niosomes
Drug Targeting
Delivery to the brain
Anti cancer drugs
Anti infectives
Targeting of bioactive agents
To Reticulo-endothelial system (RES)
To organs other than RES
NIOSOME DELIVERY APPLICATIONS
(Malhotra M et al, 1994)
51. Ophthalmic drug delivery
Delivery of peptide drugs
Immunological application of Niosomes
Transdermal delivery of drugs by Niosomes
Delivery system for the vasoactive intestinal peptide
(VIP)
Niosomes as carriers for Hemoglobin
Niosomal vaccines
NIOSOME DELIVERY APPLICATIONS
53. Unfortunately, there is not enough research conducted to
investigate toxicity of Niosomes.
It was determined that the ester type surfactants are less
toxic than ether type surfactants.
In general, the physical form of Niosomes did not
influence their toxicity as evident in a study comparing
the formulations prepared in the form of liquid crystals
and gels.
Nasal applications of these formulations caused toxicity in
the case of liquid crystal type Niosomes.
TOXICITY OF NIOSOMES
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