Abstract
Most ocular surgical procedures take ∼60 min to complete, the anaesthetic property of the safest drug, tetracaine, is initiated in a few minutes and lasts ∼10–15 min. The purpose of the present study was to develop an ocular tetracaine formulation which can produce an immediate onset of action and/or longer duration of action during the entire surgical procedure. Tetracaine-loaded microparticle formulation was prepared by the method of spray-drying and characterized in terms of size, zeta potential, morphology, thermal stability and release pattern. The study reports a microparticulate ocular formulation with minimum cytotoxicity and optimum cellular uptake. In addition, microencapsulated tetracaine was found to significantly increase the duration of action of the drug up to 4-fold. Taken together, the results presented in this work described albumin-chitosan microparticles to be an effective delivery platform for ocular anaesthetic agents and a potential treatment of various ocular diseases.