Development and Validation of Spectrophotometric Method for Determination of Levofloxacin in Rat Plasma

A simple, rapid, and cost-effective UV-Vis spectrophotometric method was developed and validated for the determination of levofloxacin in rat plasma to support the evaluation of a novel antimicrobial mesh implant containing levofloxacin, chitosan, gelatin, tinctura propolis, citric, acid and glycerin. Plasma samples were treated with 0.1 M HCl, and absorbance was measured at 290 nm. The method was validated according to FDA and ICH guidelines, including assessments of linearity, sensitivity, accuracy, precision, and specificity. The calibration curve was linear over the concentration range of 2.5-12.5 μg/mL (R² = 0.999, p < 0.001). The limit of detection and limit of quantification were 0.21 μg/mL and 0.62 μg/mL, respectively. Intra- and inter-day precision showed low relative standard deviation values (0.2% and 0.25%), while recovery ranged from 94.8% to 96.4%, confirming acceptable accuracy. No significant interference from plasma matrix components was observed. Compared with chromatographic techniques, the proposed method provides an accessible alternative for routine bioanalysis and therapeutic monitoring. The validated assay is suitable for assessing prolonged levofloxacin release from implantable drug delivery systems in preclinical studies.