Highly sensitive spectrofluorimetric determination of lomefloxacin in spiked human plasma, urine and pharmaceutical preparations

A sensitive, simple and selective spectrofluorimetric method was developed for the determination of lomefloxacin in biological fluids and pharmaceutical preparations.The method is based on the reaction between the drug and 4-chloro-7-nitrobenzodioxazole in borate buffer of pH 8.5 to yield a highly fluorescent derivative that is measured at 533 nm after excitation at 433 nm. The calibration curves were linear over the concentration ranges of 12.5–625, 15–1500 and 20–2000 ng/mL for plasma, urine and standard solution, respectively.The limits of detection were 4.0 ng/mL in plasma, 5.0 ng/mL in urine and 7.0 ng/mL in standard solution. The intra-assay accuracy and precision in plasma ranged from 0.032 to 2.40% and 0.23 to 0.36%, respectively, while inter-assay accuracy and precision ranged from 0.45 to 2.10% and 0.25 to 0.38%, respectively. The intra-assay accuracy and precision estimated on spiked samples in urine ranged from 1.27 to 4.20% and 0.12 to 0.24%, respectively, while inter-assay accuracy and precision ranged from 1.60 to 4.00% and 0.14 to 0.25%, respectively. The mean recovery of lomefloxacin from plasma and urine was 98.34 and 98.43%, respectively. The method was successfully applied to the determination of lomefloxacin in pharmaceuticals and biological fluids.

A simple and highly sensitive method is proposed for the fluorimetric determination of lomefloxacin in human plasma, urine and eye drops. The method involves the reaction of lomefloxacin with 4-chloro-7-nitrobenzodioxazole in borate buffer of pH 8.5 to give a highly fluorescent derivative that was measured at 433 nm using an excitation wavelength of 533 nm. The method was validated with the concentration range 12.5–625 ng/mL in plasma and 5–150 ng/mL in urine and the calibration curves were linear with correlation coefficients >0.999. The limits of detection were 6 ng/mL in plasma and 3 ng/mL in urine. The intra-assay accuracy and precision in plasma ranged from 0.032 to 2.40% and 0.23 to 0.36%, respectively, while inter-assay accuracy and precision ranged from 0.45 to 2.10% and 0.25 to 0.38%, respectively. The intra-assay accuracy and precision estimated on spiked samples in urine ranged from 1.27 to 4.20% and 0.12 to 0.24%, respectively, while inter-assay accuracy and precision ranged from 1.60 to 4.00% and 0.14 to 0.25%, respectively. The mean recovery of lomefloxacin from plasma and urine was 99.34 and 99.43%, respectively. The method is highly sensitive and specific. The method was successfully applied to the determination of lomefloxacin in pharmaceuticals and biological fluids.Figure optionsDownload as PowerPoint slide