This document discusses ophthalmic drug delivery systems such as contact lenses and ocular inserts. It provides information on the anatomy of the human eye, barriers to ocular absorption, and factors affecting intraocular bioavailability. Various ophthalmic preparations are classified and described, including conventional dosage forms as well as advanced drug delivery systems like nanoparticles, liposomes, and implants. Contact lenses are discussed in detail, outlining the different types and materials used as well as care solutions. Ocular inserts are introduced as controlled drug delivery devices that prolong the contact time between drugs and ocular tissues.

1. A Seminar onA Seminar on
OCUSERT & CONTACT LENSEOCUSERT & CONTACT LENSE
PRESENTED BY
MR. KIRAN N.PATANGE
M.PHARM II SEMISTER (PCEUTICS)
DEPT. OF P’CEUTICAL SCIENCES RTMNU

2. CONTENTS………
Introduction
Human eye anatomy
Mechanism of ocular absorption
Factors affecting Intraocular bioavailability
Pharmacokinetics of ocular drug
administration
Ophthalmic preparations
Classification of Ophthalmic dosage forms
Advances in ocular drug delivery

3. Ophthalmic preparations:
• Definition: They are specialized dosage forms
designed to be instilled onto the external surface of
the eye (topical), administered inside (intraocular)
or adjacent (perioccular) to the eye or used in
conjunction with an ophthalmic device.
• The most commonly employed ophthalmic dosage
forms are solutions, suspensions, and ointments.
• The newest dosage forms for ophthalmic drug
delivery are: gels, gel-forming solutions, ocular
inserts , intra-vitreal injections and implants.

4. • 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.
INTRODUCTION

5. Drugs used in the eye:
• Miotics e.g. pilocarpine Hcl
• Mydriatics e.g. Atropine
• Cycloplegics e.g. Atropine
• Anti-inflammatories e.g. corticosteroids
• Anti-infectives (antibiotics, antivirals and
antibacterials)

7. COMPOSITION OF EYE:COMPOSITION OF EYE:
Water - 98%, Solid -1.8%,
Organic element – Protein - 0.67%,
sugar - 0.65%, NaCl - 0.66%
Other mineral element sodium, potassium and
ammonia - 0.79%.

8. Human eye
Diameter of 23 m
Structure comprises of three layers
Outermost coat : The clear, transparent cornea and the
white, opaque sclera
Middle layer : The iris anteriorly, the choroid posteriorly,
and the ciliary body at the intermediate part
Inner layer : Retina (extension of CNS)
Cornea
Epithelium-stroma-endothelium
(fat-water-fat structure)
Penetration of the drug depends on Oil-water partition
coefficient
Corneal cross section

9. 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.
Lacrimal glands:
Secrete tears & wash foreign bodies.
Moistens the cornea from drying out.

10. BARRIERS IN OCULAR
ABSORPTION
Precorneal Constraints
It include –
• Solution drainage
• Lacrimation
• Tear dilution
• Tear turnover
• Conjunctival absorption
Corneal constraints
• Cornea as rate limiting barrier
• Anatomy of cornea
1.Outer-Epithelium(lipophilic),
2.Middle-Stroma(hydrophilic),
3.Inner-Endothelium(lipophilic
10

11. OCULAR ABSORPTION
11

12. OCULAR DELIVERY
SYSTEMS
CONVENTIONAL VESICULAR
CONTROL RELEASE PARTICULATE
SOLUTION
SUSPENTION
EMULSION
OINTMENT
INSERT
GELS
IMPLANTS
HYDROGELS
DENDRIMERS
IONTOPORESIS
COLLAGEN SHIELD
POLYMERIC SOLUTIONS
CONTACT LENSES
CYCLODEXRIN
MICROONEEDLE
MICROEMULSIONS
NANO SUSPENSION
ADVANCED
SCLERAL PLUGS
GENE DELIVERY
Si RNA
STEM CELL
ECT
MICROPARTICLES
NANOPARTICLES
LIPOSOMES
NIOSOMES
DISCOMES
PHARMACOSOMES

13. CONTACT LENSES:CONTACT LENSES:
 These are circular shaped structures.
 Dyes may be added during polymerization.
 Drug incorporation depends on whether their structure is
hydrophilic or hydrophobic.
Drug release depends upon :
 Amount of drug
 Soaking time.
 Drug concentration in soaking solution.
ADVANTAGES:
 No preservation.
 Size and shape
DISADVANTAGES:
 Handling and cleaning
 Expensive

14. Contact Lenses & Care Solutions:
• Types of contact lenses:
1- Hard contact lenses.
2- Soft contact lenses.
3- Rigid gas permeable (RGP).
4-Rigid hydrophobic

15. Contact Lenses & Care Solutions:
1- Hard contact lenses
- Made of rigid plastic resin polymethylmethacrylate
- Impermeable to oxygen and moisture
2- Soft contact lenses
- Made of hydrophilic transparent plastic,
hydroxyethylmethacrylate
- Contain 30 – 80% water so are permeable to oxygen
- Have two types: daily wear and extended wear

16. Contact Lenses & Care Solutions:
3- Rigid gas permeable (RGP)
- Take the advantages of both soft and hard
lenses, they are hydrophobic and oxygen
permeable.
Advantages of hard contact lenses and RGP lenses:
1- strength durability
2- resistant to absorption of medications and
environmental contaminants
3- visual acurity
Disadvantages:
1- require adjustment period of the wearer

17. Contact Lenses & Care Solutions:
• Advantages of soft contact lenses:
1- worn for longer periods
2- do not dislodge easily
Disadvantages:
1- have a shorter life span and the wearer must
ensure that the lenses do not dry out

18. • Contact Lens Classes,characteristcs & Support Product
LENS TYPE POLYMER CHARACTERISTICS SUPPORPRODUCTS
18
HARD,
RIGID,HYDROPHOBI
C
PMMA NIGLIGIBLE GAS
PERMEABILTIY,IOW
WATER
CONTENT,MEDIUM
WETTABILITY
WETTING SOLUTION
SOAKING SOLUTION
CLEANING SOLUTION
SOFT,FLEXIBLE,HYDR
OPHILIC
HEMA HIGH WATER
CONENT,LOW GAS
PERMIABILITY,GOOD
WETTABILITY,
CLEANING SOLUTION
DISINFECTION
SOLUTION
FLEXIBLE
HYDROPHOBIC
SILICONE RUBBER
SILICONE VINY
PYRROLIDONE
GOOD GAS
PERMIABILITY,POOR
WETTABILITY
WETTING SOLUTION
SOAKING SOLUTION
CLEANING SOLUTION
RIGID,HYDROPHILIC CELLULOSE ACETATE
BUTYRATE
GOOD WETTABILITY WETTING SOLUTION
SOAKING SOLUTION
CLEANING SOLUTION

19. • ADVANTAGES
• WEARER COPMFORT
• EASY ADAPTIBILITY
• ALLOW AN EASIER TRANSITION TO EYE GLASSES
• DISADVANTAGES
• REQUIRED MORE CARE
• DUE TO FLEXIBILITY ACCURATE FIT TO EYE IS MORE
DIFFICULT
• WEARER LIFE IS SHORTET THAN HARD ONE
19

20. Care of contact lenses:
• Products for soft contact lenses:
Cleaners
- To remove lipid and protein debris
- formulation:
1- viscolizing surface-active agent: to enable
gentle friction with fingertips
2- antibacterial-fast acting: benzalkonium chloride

21. Products for soft contact lenses:
• Rinsing and storage solutions
- Facilitate lens hydration,
- Inactivation of microbial contamination and
prevent the lens from drying out

22. Products for soft contact lenses:
- Rinsing and storage solutions:
- Formulation:
- 0.9% Nacl (isotonic)
- Antibacterial- 3% hydrogen peroxide for 30 min
followed by inactivation with sodium pyruvate.

23. Products for hard contact lenses:
• Rinsing and storage solutions
- For cleaning, microbial inactivation and hydration
Formulation:
- surface-active agent
- Antimicrobial:
(0.01% benzalkonium chloride + 0.1% sodium edetate )

24. Products for hard contact lenses:
Wetting solutions
- To achieve rapid wetting by the lachrymal fluid and
promot comfort
- Facilitate insertion of the lens
- Provide lubrication

25. Products for hard contact lenses:
Buffering solutions :
• Hypromellose eye drops B.P.C:
• Buffered to pH 8.4 TO 8.6 with boric acid and
borax
• These solutions better tolerated by eye as more
alkaline or acid preparations causes fogging effect.

26. Ocular inserts : Ocular
cOntrOlleD DruG DeliVerY DeVices
Definition-
Sterile preparations, with a solid or semisolid consistency
Main objective is to increase contact time between conjunctival
tissue and preparation
Inserted into the eye and worn under the upper or lower lid
Ensures a sustained and controlled release effect
Requirements for success-

27. aDVantaGes
liMitatiOns

28. classiFicatiOn
The ocular implants are flexible, oval inserts which consist of a
medicated core reservoir prepared out of a hydrogel type of
materials.
They are classified as follows
1.Insoluble inserts
 Diffusion controlled ocular inserts
 Osmotic ocular insets
 Hydrophilic matrix type ocular inserts (contact lens type)
2.Soluble inserts
3.Bio-erodible inserts
4.Implantable silicone devices
5.Implantable infusion devices
 Ocufit® &Lacrisert ®
 Minidisk ocular therapeutic system
 New ophthalmic delivery systems (NODS®)

29. . Ocular Inserts
I. Insoluble inserts:
• Insoluble insert is a multilayered structure consisting
of a drug containing core surrounded on each side by a
layer of copolymer membranes through which the drug
diffuses at a constant rate.
• The rate of drug diffusion is controlled by:
- The polymer composition
- The membrane thickness
- The solubility of the drug
e.g. The Ocusert® Pilo-20 and Pilo-40 Ocular system
- Designed to be placed in the inferior cul-de-sac between
the sclera and the eyelid and to release pilocarpine
continuously at a steady rate for 7 days for treatment of
glucoma.

30. insOluble OphthalMic inserts
Diffusion controlled ocular inserts
These consists of a medicated core prepared out of a hydrogel
polymer like alginates, sandwiched between two sheets of
transparent lipophilic, rate controlling polymer.
The drug molecule penetrate through the rate controlling
membranes at zero order rate process.
dQ/dt = Dp Km (Cr-Ct)/δm
dQ/dt = Dp Km Cs/δm (Cr >> Ct sink condition)
eg ; ocusert pilo-20

31. Synthetic and semi- synthetic polymers-
Offer additional advantage of simple design & easily
processed.
Soluble
synthetic
polymers
Cellulose derivatives- HPC, MC, HEC, HPMC, SOD. CMC
others- poly vinyl alcohol, ethylene vinyl acetate co
polymer
Additives Plasticizers- poly ethylene glycol, glycerine, propylene
glycol
complexing agent- PVP
Bioadhesives- poly acrylic acids, methyl hyroxy ethyl
cellulose
Soluble cellulose derivative inserts are composed of 30% of
water. Presence of water is unfavorable from stand point of
stability of drug.
Insert can be sterilized by exposure to gamma radiation
without the cellulose component being altered.

32. The first soluble ophthalmic drug insert (SODI)
developed was of soluble co-polymer of acrylamide, N-
vinyl pyrrolidone & ethyl acetate.
It was in form of sterile thin films or wafers or oval
shape, weighing 15 – 16 mg.
A new type of ophthalmic insert incorporating a
water- soluble bio-adhesive component in its formulation
has been developed to decrease risk of expulsion &
ensure prolonged residence in eye, combined with the
controlled release.
These inserts, named bio-adhesive ophthalmic drug
inserts (BODI)

33. II.Soluble Ocular inserts:
Lacrisert is a sterile ophthalmic insert use in the treatment of dry
Eye syndrome and is usually recommended for patients unable
to obtain symptomatic relief with artifical tear solutions.
The insert is composed of 5 mg of Hydroxypropyl cellulose
in a rod-shaped form about 1.27 mm diameter by about 3.5 mm
long.

34. II.Soluble Ocular inserts:
- Soluble inserts consists of all monolytic polymeric
devices that at the end of their release, the device
dissolve or erode.
Types
a) Based on natural polymers e.g. collagen.
b) Based on synthetic or semi synthetic polymers e.g.
Cellulose derivatives – Hydroxypropyl cellulose,
methylcellulose or Polyvinyl alcohol, ethylene vinyl
acetate copolymer.
- The system soften in 10-15 sec after introduction into
the upper conjunctival sac, gradually dissolves within
1h , while releasing the drug.
- Advantage: Being entirely soluble so that they do not
need to be removed from their site of application.

35. BIO ERODIBLE INSERTS
Main component of this type of inserts is the bio-erodible
polymers.
They undergoes hydrolysis of chemical bonds & hence
dissolution.
Bio-erodible matrix controlling the release rate of the drug
ensures zero order release rate.
Eg., poly (ortho esters), poly (ortho carbonates)
Great advantage of these bio-erodible polymers is the
possibility of modulating their erosion rate by modifying
their final structure during synthesis.

36. ImpLaNTaBLE SILIcONE DEvIcES
Developed for the local delivery of an anti-neoplastic
drug to the intra-ocular site.
Composed of 2 sheets of silicone rubber glued to the
edge with adhesive to form a balloon like sac through
which a silicone tubing (0.3 mm dia) is inserted.
Such devices have significant potential for local
controlled delivery of anti- bacterial, anti-cancer, & anti-
viral drugs to anterior chamber of eye.

37. OThER DELIvERy DEvIcES
Ocufit® is a sustained release rod shape device made up of
silicone elastomer.
Lacrisert® is another cylindrical device, which is made of HPC
and used for treating dry- eye patients.
Mini disk ocular therapeutic systems (OTS)- It is a miniature
contact lens shaped, made of silicone based pre polymer. It
requires less time & less manual dexterity for insertion, when
compared with lacrisert®.
New ophthalmic delivery system (NODS)- It is a method for
delivering precise amounts of drugs to eye within a water
soluble, drug- loaded film.
When evaluated in humans, the NODS produced an 8 fold
increase in BA for pilocarpine with respect to std. eye drop
formulations.

38. pREpaRaTION Of OcuLaR INSERT
Casting method

39. chaRacTERIzaTION Of INSERTS
Uniformities of weight & thickness
Uniformities of drug content
Surface PH
In-vitro release studies (continuous flow through apparatus)
Ocular irritation test
In-vitro microbial studies

40. pacKaGING
Ophthalmic insert 5 mg supplied in packages of 60
sterile unit dosage forms.
Each wrapped in an aluminum blister.
With two reusable applicators.
A plastic storage container to store the applicators for
use.

41. hOw TO uSE
•To apply the system, wash hands first.
•Tilt your head back, gaze upward and pull down the
lower eyelid to make
a pouch.
•Place the system into the pouch.
•Blink a few times and roll your eye to move the insert into
place.
•Practice inserting and removing the system in the doctor
s office where
you can be shown the proper technique.
•Damaged or deformed systems should not be used or kept
in the eye.
•Replace with a new system.

42. Advances in ocular drug deliveryAdvances in ocular drug delivery
11. Ophthalmic gel for pilocarpine. Ophthalmic gel for pilocarpine
Poloxamer 407 (low viscosity, optical clarity, mucomimetic
property)
2. Ophthalmic prodrug2. Ophthalmic prodrug
Dipivalyl epinephrine (Dipivefrin)
Lipophilic  increase in corneal absorption
Esterase within cornea and aqueous humor
3. Continuous delivery system based upon the osmotic property3. Continuous delivery system based upon the osmotic property
Thin flat layer, contoured three-dimensional unit
Conform to the space of the upper cul-de-sac
Delivery of diethyl carbamazine in ocular onchocerciasis

43. 4. Gel delivery system4. Gel delivery system
Biodegradable polyisobutyl-cyano acrylate (PIBCA)
colloidal particulate system of pilocarpine to incorporate it
into a Pluronic F127 (PF 127)-based gel delivery system.
5. Mucoadhesive Polymer.
Mucoadhesive polymer, the tamarind seed polysaccharide,
as a delivery system for the ocular administration of
hydrophilic and hydrophobic antibiotics.

44. THANK U…
“ Sight is the sense which is more
valuable than all the rest”
So Take Care Of Eyes!!!!!!