ABSTRACT
Ocular inserts of gentamicin sulfate with polyvinyl alcohol (PVA) 1.5%, 2.0%, and 2.5% and a combination of methyl cellulose 2% and Eudragit NE 30D 30%, 35%, and 40% w/w of methyl cellulose were fabricated by a casting technique. The inserts were sterilized by gamma radiation at 25 kGy and tested for sterility. The microbiological efficacy of the ocular inserts against Staphylococcus aureus ATCC 6538P and Pseudomonas aeruginosa NCIM 2200 was evaluated by developing an in vitro microbiological model and an in vivo noninvasive rabbit eye model. Parameters of the in vitro microbiological model were varied, and the results correlated with a noninvasive rabbit eye model. The in vitro model proved to be a viable alternative to the rabbit eye model in evaluating the microbiological efficacy of gentamicin sulfate ocular inserts.
Subject(s)
Animal Testing Alternatives/methods , Eye/microbiology , Gentamicins/administration & dosage , Pseudomonas aeruginosa/drug effects , Staphylococcus aureus/drug effects , Administration, Topical , Animals , Evaluation Studies as Topic , In Vitro Techniques , Male , Models, Biological , Polyvinyl Alcohol/chemistry , Rabbits , Time FactorsABSTRACT
High-performance thin-layer chromatographic (HPTLC) analysis of gentamicin by in situ fluorodensitometric evaluation of its 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) derivative is presented. The aminoglycoside components separated on silica gel plates using chloroform-methanol-20% ammonium hydroxide (2.4:2.2:1.5, v/v/v) as the mobile phase were reacted with NB-Cl to yield highly fluorescent derivatives. The calibration curves of gentamicin in water, plasma and urine were linear in the range 40-200 ng. The mean values of intercept, slope and correlation coefficient were 16.82 +/- 0.473, 6.83 +/- 0.015 and 0.9968 +/- 0.0017 for standard curves in water, 17.35 +/- 0.375, 6.85 +/- 0.018 and 0.9941 +/- 0.0012 for standard curves in plasma and 14.35 +/- 0.286, 6.86 +/- 0.002 and 0.9933 +/- 0.0011 for standard curves in urine respectively. The analytical technique was validated for within-day and day-to-day variation. The results indicate that HPTLC, coupled with in situ fluorodensitometry, is a reliable and valuable technique for quantitative analysis of the bulk drug gentamicin and gentamicin from urine and plasma.
