Nanogels for Topical Drug Delivery in Ocular Diseases

The eye is an extremely delicate organ in human. There are several challenges for people in preventing and healing of eye illnesses.

Topical drug delivery, the noninvasive technique that is most frequently used to treat ocular diseases which provides adequate doses of drug ingredients to the inside of eye over time. For many ocular diseases such as glaucoma, cataracts, dry eye syndrome, and inflammatory infections, eye drops are traditionally the first line of treatment. Apart from eye drops, traditional ocular formulations such as ointments, suspensions, lotions, and so on are also frequently found in the market in addition to eye drops and include. They improve the bioavailability and extend the period of drug retention time in the eye, but they have disadvantages.

Additionally, the anatomical and physiological barriers of the eye limit usage of traditional ocular preparations, which presents a serious problem for doctor, patients, and pharmacists in that it results in a short retention time period and poor bioavailability of the medicationThe research and development of various ophthalmic formulations that have been used in the past few years, such as micelles, liposomes, nanoparticles, nanosuspensions, dendritic polymers, microneedles, cubosomes, niosomes, nanowafers, etc., offer several alternatives to the drug delivery of traditional ophthalmic formulations.

However, Drugs can be encapsulated in three-dimensional cross-linked polymeric networks using nanogels.This allows for the controlled and sustained delivery of loaded drugs, improving patient compliance and therapeutic efficiency. Furthermore compared to nanocarriers, nanogels have a higher drug-loading capacity and more biocompatibility. 

Advantages of Nanogels

For several reasons nanogels are considered advantageous than other drug delivery systems:

1. Biocompatibility and degradability: Polymers, either synthetic or natural, are employed in the creation of nanogel. Their excellent biocompatibility and biodegradability prevent them from building up in organs.
2. Swelling characteristics in aqueous media: They can absorb and hold enormous amounts of water due to their tremendous love for water, which causes swelling. This swelling characteristic is important for a number of applications, including the administration of drugs.
3. High drug loading capacity: Due to their small size and high area of surface to volume ratio, nanogels are well suited for the effective loading of pharmaceuticals. Compared to bigger particles or traditional dosage forms, their porosity nature allows for more space for drug molecules to be encapsulated or attached, which results in a better drug loading capacity.
4. Non-immunologic response: Nanogels have been designed to reduce the body’s immune responses. When used as drug delivery vehicles or in other biomedical applications, their inert nature in the bloodstream and internal aquatic ecosystems helps to ensure that they do not provoke major immune reactions.
5. Ease of synthesis: Nanogel synthesis is a stress-free process, which don’t require mechanical energy and can be carried out under mild conditions. This nanogel synthesis methods aim to minimize or eliminate the use of organic solvents. Therefore the drug can be loaded effortlessly without being subjected to any robust conditions throughout the preparation process.
6. High encapsulation stability: Maximizing therapeutic results while minimizing toxicity or adverse effects is the constant objective.

This review, concentrate on Nanogels have emerged as promising tools in the treatment of various ocular disorders due to their unique properties and versatility. Enhancing our understanding of topical drug delivery will need be improved regarding the advancement of nanogels in common ocular diseases, such as glaucoma, cataracts and dry eye syndrome.

References:

1.Bourne R., Steinmetz J.D., Flaxman S., Briant P.S., Taylor H.R., Resnikoff S., Casson R.J., Abdoli A., Abu-Gharbieh E., Afshin A.,. Vision Loss Expert Group of the Global Burden of Disease Study Trends in Prevalence of Blindness and Distance and near Vision Impairment over 30 Years: An Analysis for the Global Burden of Disease Study. Lancet Glob. Health. 2021;9:e130–e143. 

2.Awwad S., Mohamed Ahmed A.H.A., Sharma G., Heng J.S., Khaw P.T., Brocchini S., Lockwood A. Principles of Pharmacology in the Eye. Br. J. Pharmacol. 2017;174:4205–4223. 

Dr. PRIYANKA SAHARAN

ASSOCIATE PROFESSOR

FACULTY OF PHARMACY, KALINGA UNIVERSITY