The Development and Characterization of Eye Drops Containing Acyclovir Microspheres against Herpes Simplex-induced Keratitis

Abstract

Objective: Acyclovir (ACV), a highly specific inhibitor of herpes virus replication, is applied topically
into the eye to treat ocular keratitis. The main aim of this study was to formulate and characterize eye drops
containing ACV microspheres against herpes simplex-induced keratitis. The microspheres are small spherical
particles with diameters ranging from 10 to 1000 μm. It increases bioavailability while decreasing side effects.
Materials and Methods: The solvent evaporation technique was used to develop the microspheres for the
sustained release drug delivery system. Crystalline methylcellulose, sodium alginate, calcium chloride, and
chitosan were the polymers used. The drug content, encapsulation efficiency, in vitro drug release studies, stability
studies, viscosity, pH measurement, and clarity test were all performed on the microspheres. Results: Particle size
and shape, percent entrapment, in vitro drug release, compatibility studies, and other characteristics of microsomes
were assessed. These drug delivery systems demonstrated good increased solubility and sustained release, which is
necessary for bioavailability and therapeutic action, due to their matrix nature. The formulation has an acceptable
shape and particle size, no chemical interactions, and is stable under refrigeration, according to the results of the
characterization parameters and stability research. Conclusion: Eye drops containing microspheres of ACV could
be considered a promising sustained drug delivery system for ocular keratitis treatment.