EVALUATION OF THE THERAPEUTIC EFFECTIVENESS AND SUSTAINED RELEASE CAPACITY OF LEVOFLOXACIN LOADED SILICONE HYDROGEL CONTACT LENSES
ULOMA NKECHINYERE UBANI-UKOMA*, JEMIMA IFUNANYA EGBO, JESSICA CHINENYE EZIMOHA, TOLULOPE OLUBUKONLA OLUWOLE, MARGARET OKONAWAN ILOMUANYA, BOLADALE OLANREWAJU SILVA
Department of Pharmaceutics & Pharmaceutical Technology, Faculty of Pharmacy, University of Lagos, Nigeria.
Afr. J Pharm Res Dev; Volume 14(2): 119-127 ; 2022
ABSTRACT
Eye infections are mostly managed by multiple instillations of antimicrobial eye drops throughout the duration of treatment. This study compares the effectiveness of a sustained release levofloxacin eluting hydrogel contact lens with conventional eye drop in the treatment and management of ocular surface infections. Two silicone hydrogel contact lenses (Senofilcon A and Narafilcon A) were modified by incorporating levofloxacin by soaking method. Vitamin E (α-tocopherol) was incorporated as diffusion barrier using ethanolic vitamin E solvent. The modified lenses were characterized for loading, transmissibility, and release kinetics. The efficacy of the select hydrogel was compared with levofloxacin eye drop against Staphylococcus aureus and Pseudomonas aeruginosa using modified Kirk Bauer disk diffusion method. The senofilcon A levofloxacin loaded lens released approximately 80% of the drug in 45 mins while just about 30% of the drug was released at the same time by narafilcon A lens. The transmissibility of both lenses after modification were above 90% and drug release was shown to be by Higuchi model and Fickian diffusion in both levofloxacin lenses and vitamin E loaded lenses. Narafilcon A modified lenses with and without diffusion barrier showed comparative antimicrobial effectiveness with 5% levofloxacin eye drop against Pseudomonas aeruginosa and Staphylococcus aureus. Levofloxacin release from 10% vitamin E loaded lens showed sustained release without any burst effect. Levofloxacin narafilcon A eluting contact lens can be employed as a suitable sustained release alternative to multiple instillations of eye drops in the treatment and management of anterior ocular bacterial infections.
Email of correspondence: uubani-ukoma@unilag,edu.ng;
KEYWORDS: Sustained release; ocular infections; Hydrogel lens; vitamin e; Pseudomonas aeruginosa; Staphylococcus aureus.