A REVIEW ON RECENT TRENDS AND FUTURE PERSPECTIVES OF IONTOPHORESIS ASSISTED OCULAR DRUG DELIVERY

Iontophoresis assisted drug delivery system refers to a novel system for delivery of the drug in a non-invasive and effective manner across the skin or biological membranes by electrical assistance. Drug substances exhibiting low trans-corneal (ocular) permeability can be effectively delivered in a safe, fast, and painless manner by the employment of electric current of low intensity, which enhances permeation of drugs across the cornea and thereby, extends the duration of drug action. Fundamental principles of physics guide the technique of ocular iontophoresis that repulsion occurs between the ionic charges of the same nature, while attraction occurs between the ionic charges of opposite nature. Electro-repulsion and electro-osmotic flow are the two transport mechanisms on which ocular iontophoresis works. For the ocular delivery of the drug, there are various iontophoresis devices available in the market, e.g., Eyegate^® II and OcuPhore^®, those are the most commonly used delivery devices for this purpose, while Visulex^TM is another similar system. On the basis of the site of application, ocular iontophoresis can be classified as trans-scleral and trans-corneal. This review paper is aimed to provide a comprehensive and comparative account of the development of ocular iontophoresis devices comparing their principle, factors affecting iontophoretic drug delivery, their therapeutic applications, and future prospects.