Bacterial
keratitis in animals presents challenges due to ocular structural barriers, hindering effective
drug delivery. In this study, we used biocompatible and biodegradable
poly(lactic-co-glycolic acid) (PLGA) to encapsulate the naturally occurring
antimicrobial peptide OH-CATH30, an alternative to conventional
antibiotics, for the treatment of bacterial
keratitis in animals.
Microspheres (MS) were prepared using a modified water-in-oil-in-water (W/O/W) double-
emulsion method with optimized osmotic pressure. We conducted comprehensive evaluations, including in vitro characterization, encapsulation efficiency determination, in vitro release kinetics, and in vivo/vitro assessments of irritation and bacterial inhibition. The optimized method yielded
microspheres with impressive encapsulation efficiency of 75.2 ± 3.62% and a loading capacity of 18.25 ± 5.73%, exhibiting a well-defined particle size distribution (200-1000 nm) and a ΞΆ-potential of -17.3 ± 1.91 mV. The
microspheres demonstrated initial burst release followed by sustained and controlled release in vitro. Both in vitro and in vivo tolerance tests confirmed the biocompatibility of the
drug-loaded
microspheres, as they did not elicit significant irritation in ocular tissues. Remarkable antibacterial effects were observed in both in vitro and in vivo experiments. Our developed PLGA
microspheres show promise as an alternative therapeutic option for
topical administration in managing
keratitis, offering exceptional
drug delivery capabilities, improved bioavailability, and potent antibacterial efficacy.