Barrier of drugs permeation through ocular route by Sushil Kumar SinghSushil Singh
Barriers of Drugs Permeation Through Ocular Route. this topic explain about ocular route and barriers system. and classification of different injection routes takes the ocular drugs.
Barrier of drugs permeation through ocular route by Sushil Kumar SinghSushil Singh
Barriers of Drugs Permeation Through Ocular Route. this topic explain about ocular route and barriers system. and classification of different injection routes takes the ocular drugs.
Contents
Introduction
Objective
Anatomy of the Eye
Routes of drug delivery of the eye
Mechanism of ocular absorption
Factors affecting intra-ocular bioavailability
Barriers of ocular drug absorption
Methods to overcome drug barriers
Evaluation
Conclusion
Reference
Ocular administration of drug is primarily associated with the need to treat ophthalmic diseases.
Applied topically to the cornea, or instilled in the space between the eyeball and lower eyelid
Definition: Ocular DDS are designed to instilled on to topical or intra-ocular or peri-ocular to eye.
Most commonly used ocular dosage forms-
- Solutions
- Suspensions
- ointments
Ideal ophthalmic drug delivery must be able to sustain the drug release and to remain in the vicinity of front of the eye for prolong period of time.
The presentation includes Introduction to Ocular Drug Delivery System, Anatomy of Human eye, Mechanism of Ocular Drug Absorption, Barriers for Ocular Delivery, Factors affecting Intraocular bioavailability, Drawbacks of traditional ophthalmic formulations, Classification of Ocular Drug Delivery System, Formulations of Ocular Drug Delivery System and Evaluation parameters of Ocular Drug Delivery System.
An overview of Bio/Mucoadhesive drug delivery system covering various aspects like advantages, approaches, mechanism of mucoadhesion, various theories, various testing methods and examples of marketed preparations.
Introduction
Anatomy and physiology of human eye
Ocular delivery system
Optimum characters of ophthalmic drugs
Routes of ophthalmic drugs
Mechanism of ocular drug absorption
Barriers and fate of ocular drug delivery
Formulation consideration of ocular dosage forms
Evaluation tests
References
FORMULATION AND EVALUATION OF OCUSERTS OF CIPROFLOXACIN HClMohammad Adil
Conventional ocular drug delivery system i.e., eye drops, ointments, gels etc., had become less popular pertaining to their disadvantages like evaporation by tears, pre-corneal loss, drug metabolism, drug-protein interaction, drainage, sticking of eye lids, induced lacrimation, poor patient compliance, systemic side effect and blurred vision etc. That’s why fundamentals of controlled release by means of ocular inserts were utilized to increase problem pre-corneal drug residence time.
This project title “Formulation and Evaluation of Ocuserts of Ciprofloxacin HCl” revealed following results:
Compatibility study using FTIR was performed to check the compatibility of drug with various excipient. Characteristics peaks obtained with pure drug were compared with that produced with different excipients that confirmed the compatibility of drug with excipients.
Ocusert of Ciprofloxacin HCl was prepared using different material i.e., PVP K-30, PVA, PEG 400 and glycerin.
Prepared ocuserts were evaluated for various parameters viz., percentage moisture loss, percentage moisture absorbs, thickness, weight variation, drug content and In-vitro diffusion.
The percentage (%) moisture absorption and loss of ocular insert were found to be 26% and 27% respectively.
The thickness of ocular insert was found to be uniformed and its mean while measuring at different points was found to be 0.124mm.
The weight of ocular inserts was found to be in the range of 12.2 - 12.6mg which indicated decent distribution of the drug, polymer and plasticizer.
The drug content of ocular insert was found to be 99.89%.
Percentage drug release from Ciprofloxacin HCl Ocusert was found to be 41.969% in 8 hr.
It was concluded that prepared Ocusert of Ciprofloxacin HCl could be a better alternative to conventional ocular formulations that retained on ocular surface for longer duration and released drug in controlled manner.
Contents
Introduction
Objective
Anatomy of the Eye
Routes of drug delivery of the eye
Mechanism of ocular absorption
Factors affecting intra-ocular bioavailability
Barriers of ocular drug absorption
Methods to overcome drug barriers
Evaluation
Conclusion
Reference
Ocular administration of drug is primarily associated with the need to treat ophthalmic diseases.
Applied topically to the cornea, or instilled in the space between the eyeball and lower eyelid
Definition: Ocular DDS are designed to instilled on to topical or intra-ocular or peri-ocular to eye.
Most commonly used ocular dosage forms-
- Solutions
- Suspensions
- ointments
Ideal ophthalmic drug delivery must be able to sustain the drug release and to remain in the vicinity of front of the eye for prolong period of time.
The presentation includes Introduction to Ocular Drug Delivery System, Anatomy of Human eye, Mechanism of Ocular Drug Absorption, Barriers for Ocular Delivery, Factors affecting Intraocular bioavailability, Drawbacks of traditional ophthalmic formulations, Classification of Ocular Drug Delivery System, Formulations of Ocular Drug Delivery System and Evaluation parameters of Ocular Drug Delivery System.
An overview of Bio/Mucoadhesive drug delivery system covering various aspects like advantages, approaches, mechanism of mucoadhesion, various theories, various testing methods and examples of marketed preparations.
Introduction
Anatomy and physiology of human eye
Ocular delivery system
Optimum characters of ophthalmic drugs
Routes of ophthalmic drugs
Mechanism of ocular drug absorption
Barriers and fate of ocular drug delivery
Formulation consideration of ocular dosage forms
Evaluation tests
References
FORMULATION AND EVALUATION OF OCUSERTS OF CIPROFLOXACIN HClMohammad Adil
Conventional ocular drug delivery system i.e., eye drops, ointments, gels etc., had become less popular pertaining to their disadvantages like evaporation by tears, pre-corneal loss, drug metabolism, drug-protein interaction, drainage, sticking of eye lids, induced lacrimation, poor patient compliance, systemic side effect and blurred vision etc. That’s why fundamentals of controlled release by means of ocular inserts were utilized to increase problem pre-corneal drug residence time.
This project title “Formulation and Evaluation of Ocuserts of Ciprofloxacin HCl” revealed following results:
Compatibility study using FTIR was performed to check the compatibility of drug with various excipient. Characteristics peaks obtained with pure drug were compared with that produced with different excipients that confirmed the compatibility of drug with excipients.
Ocusert of Ciprofloxacin HCl was prepared using different material i.e., PVP K-30, PVA, PEG 400 and glycerin.
Prepared ocuserts were evaluated for various parameters viz., percentage moisture loss, percentage moisture absorbs, thickness, weight variation, drug content and In-vitro diffusion.
The percentage (%) moisture absorption and loss of ocular insert were found to be 26% and 27% respectively.
The thickness of ocular insert was found to be uniformed and its mean while measuring at different points was found to be 0.124mm.
The weight of ocular inserts was found to be in the range of 12.2 - 12.6mg which indicated decent distribution of the drug, polymer and plasticizer.
The drug content of ocular insert was found to be 99.89%.
Percentage drug release from Ciprofloxacin HCl Ocusert was found to be 41.969% in 8 hr.
It was concluded that prepared Ocusert of Ciprofloxacin HCl could be a better alternative to conventional ocular formulations that retained on ocular surface for longer duration and released drug in controlled manner.
INTRODUCTION :
Ocular administration of drug is primarily associated with the need to treat ophthalmic diseases.
Eye is the most easily accessible site for topical administration of a medication.
Ideal ophthalmic drug delivery must be able to sustain the drug release and to remain in the vicinity of front of the eye for prolong period of time.
The bioavailability of ophthalmic drugs is very poor due to efficient protective mechanisms of the eye.
Blinking, reflex lachrymation, and drainage rapidly remove drugs, from the surface of the eye.
To overcome these, two approaches can be followed.
The first involves using alternate delivery routes to conventional ones allowing for more direct access to intended target sites.
Second approach involves development of novel drug delivery systems providing better permeability, treatability and controlled release at target site.
Combination of both these approaches are being utilized and optimized in order to achieve optimal therapy with minimal adverse effects.
ocular drug delivery system (ODDS) barriers, rought of administrationkishan singh tomar
Ocular drug delivery systems are specialized formulations designed to efficiently deliver medications to the eye for the treatment of various ocular conditions. These systems overcome the challenges posed by the eye's natural barriers, such as tear dilution and rapid clearance, to ensure optimal drug absorption and efficacy.
One common type of ocular drug delivery system is eye drops, which deliver medications directly onto the ocular surface. However, traditional eye drops often suffer from poor bioavailability and require frequent administration due to rapid drainage and clearance. To address these limitations, researchers have developed innovative formulations, including nanoparticles, liposomes, and hydrogels, which can prolong drug retention on the ocular surface and enhance corneal penetration.
Another approach involves intraocular implants, such as drug-eluting devices or sustained-release inserts, which can provide controlled release of medication over an extended period. These implants offer the advantage of reducing the need for frequent dosing and improving patient compliance.
Additionally, advancements in nanotechnology have led to the development of nanoscale drug delivery systems that can target specific tissues within the eye, such as the retina or the aqueous humor, while minimizing systemic side effects.
Overall, ocular drug delivery systems represent a promising area of research aimed at improving the treatment outcomes of various ocular diseases, including glaucoma, macular degeneration, and dry eye syndrome, by optimizing drug delivery efficiency and minimizing adverse effects.
Ocular drug delivery system - NDDS - B.PHARMAJafarali Masi
Ocular drug delivery system - NDDS - B.PHARMA
Introduction, intra ocular barriers and methods to overcome –Preliminary study, ocular formulations and ocuserts
ocular drug delivery systems in drug delivery systemsArun Pandiyan
DEFENITION:
Drug delivery systems are designed to enhance the targeted delivery of medications, improving their effectiveness while minimizing side effects. Various approaches include nanoparticles, liposomes, and implantable devices, offering controlled release or targeted delivery to specific tissues. These systems aim to optimize therapeutic outcomes and patient compliance.
CLASSIFICATION OF DRUG DELIVERY SYSTEM
Oral Drug Delivery:- Tablets, capsules, and liquids are commonly used for systemic drug delivery. Controlled-release formulations provide sustained drug release over time
Injectable Drug Delivery:- Intravenous, intramuscular, and subcutaneous injections allow rapid drug delivery into the bloodstream. Depo injections provide sustained release over weeks or months.
Transdermal Drug Delivery:- Patches and topical formulations deliver drugs through the skin. Ensures a controlled and prolonged release of medication.
Inhalation Drug Delivery:- Aerosolized medications for respiratory conditions. Rapid absorption through the lung's extensive surface area.
Implantable Drug Delivery:- Devices like pumps or reservoirs placed under the skin for continuous drug release. Common for long-term conditions requiring a steady dosage.
Nanoparticle-based Drug Delivery:- Nanocarriers (liposomes, micelles, nanoparticles) enhance drug solubility and improve targeted delivery. Effective for delivering drugs to specific cells or tissues.
Targeted Drug Delivery:- Ligand-based systems use specific molecules to target drugs to particular cells or tissues. Minimizes side effects by focusing on diseased areas.
Gastrointestinal Drug Delivery:- Drug formulations designed for specific release in different parts of the gastrointestinal tract. Examples include enteric-coated capsules.
Intrathecal Drug Delivery:- Direct delivery of drugs into the spinal canal. Often used for pain management or neurological conditions.
Ocular Drug Delivery:- Eye drops, ointments, or implants for treating ocular conditions. Ensures targeted drug delivery to the eyes.
These systems cater to diverse medical needs, offering tailored solutions for optimal therapeutic outcomes.
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
Introduction to AI for Nonprofits with Tapp NetworkTechSoup
Dive into the world of AI! Experts Jon Hill and Tareq Monaur will guide you through AI's role in enhancing nonprofit websites and basic marketing strategies, making it easy to understand and apply.
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Acetabularia acetabulum is a single-celled green alga that in its vegetative state is morphologically differentiated into a basal rhizoid and an axially elongated stalk, which bears whorls of branching hairs. The single diploid nucleus resides in the rhizoid.
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
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Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
Macroeconomics- Movie Location
This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
1. Presented By:
Ruchi Pal
M. Pharm. (Pharmaceutics)
2nd Sem. 2019-20 Batch
Ocular Drug Delivery System
CSJM University Kanpur
University Institute of Pharmacy
3. INTRODUCTION
Pharmaceutical preparation that are applied topically to the eye for the treatment of
surface and intra ocular dysfunction are called Ocular Drug Delivery System.
Ocular administration of drug is primarily associated with the need to treat ophthalmic
diseases.
Advantages-
1.Increased accurate dosing , To overcome the side effects .
2.To provide sustained and controlled drug delivery.
3.To increase the ocular bioavailability of drug .
4.To provide targeting within the ocular globe , prevent the loss to other ocular tissues.
5.To provide comfort , better compliance .
5. Fluid systems in eye
1. Aqueous humor
● Secreted from blood
through epithelium of the
ciliary body.
● Secreted in posterior
chamber and transported to
anterior chamber.
2. Vitreous humor
● Secreted from blood
through epithelium of the
ciliary body.
● Diffuse through the vitreous
body.
6. Mechanism of Ocular Absorption
1.Non - corneal absorption:
● Penetration across sclera & conjunctiva into intra ocular tissues.
● Non productive - because penetrated drug is absorbed by
general circulation.
2.Corneal absorption:
● Outer epithelium - Pore size 60 only access to small ionic and
lipophilic molecules.
● Trans cellular transport - transport between corneal epithelium
and stroma.
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9. Pre-Corneal Barrier Post-Corneal Barrier
Drainage Post Corneal Absorption
Lacrimation Post Sclera Absorption
Tear Dilution Enzymatic Degradation
Drug Protein Binding
Drug Metabolism
Nasolacrimal Drainage
Nasolacrimal Drainage - Tear flow from the external eye to the
nasal cavity
Lacrimation - Abnormal secretion of tears.
10. ● Sterility
● Isotonicity - eg 1.9% boric acid, 0.9% NaCl
● Buffer/pH adjustment
● Less drainage tendency
● Minimum protein binding
● Non Toxic
IDEAL CHARACTERISTICS OF ODDS
12. INSERTS CLASSIFICATION
1. NON ERODIBLE INSERTS
i. Ocusert
ii. Contact lens
2. ERODIBLE INSERTS
i. Lacriserts (Sterile rod shaped device made up of propyl cellulose without any
preservative)
ii. SODI (soluble ocular drug inserts)
iii. Minidisc (4 to 5 mm).
13. Ocuserts
● A retaining ring of the same material
impregnated with titanium dioxide encloses the
drug reserve oil.
● When this is placed under the upper or lower
eyelid, the pilocarpine molecules dissolves in
the lacrimal fluid and releases at predefined
rates.
● Ocular insert (Ocusert) are sterile preparation
that prolong residence time of drug with a
controlled release manner.
14. •
Lacriserts
.This is an sterile rod shape device i.e. placed in our
eye to treat dry eyes.
.It is usually use when an artificial tears solution is
not successful .
.This medication may also be used to treat certain
other eye disorders (Keratitis, decreased corneal
sensitivity).
.Inserted into Inferior fornix.
.Composition-Propyl cellulose(without preservative)
15. Liposomes
● Biocompatible and biodegradable lipid vesicles made up of natural
lipids and about 25–10 000 nm in diameter.
● Limitations - Liposomes are chemical instability, oxidative degradation
of phospholipids, cost and purity of natural phospholipids.
Niosomes
● Chemically stable and can entrap both hydrophobic and hydrophilic
drugs.
● Non-ionic surfactant vesicles that have potential applications in the
delivery of hydrophobic or amphiphilic drugs.
16. Pharmacosomes
● When they were administered into the eye,
the lysosomal enzymes cause cleavage of
drug from the glyceride moiety.
Discomes
• They are large structures formed by
solubilisation of niosomes with a non-ionic
surfactant.
• They act as drug reservoirs, as they are
capable of entrapping water soluble solutes.
17. EVALUATION OF ODDS
● THICKNESS OF THE FILM
● DRUG CONTENT UNIFORMITY
● UNIFORMITY OF WEIGHT
● PERCENTAGE MOISTURE ABSORPTION
% moisture absorbed = Final weight – initial weight/initial weight x 10
In-Vitro EVALUATION METHODS
● BOTTLE METHOD
● DIFFUSION METHOD
>MODIFIED ROTATING BASKET METHOD
>MODIFIED ROTATING PADDLE APPARATUS
18. Limitations
1.Interference with vision.
2.Dosage form can not be terminated during emergency
3.Poor Patient Compliance .
4. Difficulty in placement and removal.
5. Occasional lose during sleep or while rubbing eyes.
6. Movement around the eye.
19. References:
• Brahmankar D. M., Jaiswal B., “Biopharmaceutics and Pharmacokinetics” - A
Treatise Vallabha Prakashan; Third Edition (2019) Page No. 473-476.
• Jain N. K., “Advances In Controlled & Novel Drug Delivery” CBS Publication,
First Edition 1997 Page No. 82-96.
• Gote. V, Sikder. S, Sicotte. J & Pal. D “Ocular Drug Delivery: Present
Innovations and Future Challenges” Journal Of Pharmacology and
Experimental Therapeutics. May 9 2019.
• Bhavishkar T. D., Jain K. D. “Novel Drug Deliver Systems” Nirali Prakashan
First Edition. 2012. Page No. 112-119.
