Application of Response Surface Modeling and Chemometrics Methods for the Determination of Ofloxacin in Human Urine Using Dispersive Liquid-Liquid Microextraction Combined with Spectrofluorimetry

Farah Assadian,Ali Niazi

doi:10.21577/0103-5053.20170080

Abstract

Dispersive liquid-liquid microextraction (DLLME) and spectrofluorimetry, coupled with chemometrics methods, are proposed in this work for the pre-concentration and determination of ofloxacin concentration in spiked human urine. Chloroform and acetonitrile were selected as the extraction and dispersive solvents by the one-variable-at-a-time process. The Box-Behnken design was used to optimize the other variables, including the volume of extraction and dispersion solvents, solution pH, and ionic strength. A linear calibration curve was obtained in the 5.0-120.0 ng mL-1 range under optimal conditions with a detection limit of 1.61 ng mL-1 and correlation coefficient of 0.9948. A relative standard deviation (RSD) of 1.13% was obtained for seven consecutive replicates. Parallel factor analysis (PARAFAC) and partial least square (PLS) modeling were applied for the multivariate calibration of the spectrofluorimetric data. To pre-process the data matrices and predict the model results, the orthogonal signal correction (OSC) was used, and the analysis results were statistically compared. The methods accuracy values for ofloxacin determination, evaluated by the root mean square errors of prediction (RMSEP) and relative standard error of prediction (RSEP), were 0.82 and 1.12 using OSC-PLS, and 0.31 and 0.42 using OSC-PARAFAC models, respectively. Ofloxacin can be reliably determined in human urine samples through the proposed procedure, according to the results.

Highlights

A second-generation fluoroquinolone, ofloxacin (OFL, 9-fluoro-2,3-dihydro-3-methyl-10-(4-methyl1-piperazine)-7-oxo-7H-pyrido[1,2,3-de]1,4‐benzoxazine-6-carboxylic acid) is a synthetic antibiotic of the fluoroquinolone drug family (Figure 1).[1]
Box-Behnken design (BBD) was used to optimize the effective levels of variables in the extraction of the ofloxacin and response surface methodology (RSM) was applied to analyze the effect of the independent factors on the response, in order to evaluate the relative significance of several affecting factors
Dispersive liquid-liquid microextraction (DLLME) has been coupled with spectrofluorimetry for the extraction and determination of ofloxacin in several different samples such as biological and pharmaceutical formulations samples in this work

Summary

Introduction

A second-generation fluoroquinolone, ofloxacin (OFL, 9-fluoro-2,3-dihydro-3-methyl-10-(4-methyl1-piperazine)-7-oxo-7H-pyrido[1,2,3-de]1,4‐benzoxazine-6-carboxylic acid) is a synthetic antibiotic of the fluoroquinolone drug family (Figure 1).[1]. High-performance liquid chromatography (HPLC),[4,5,6] spectrophotometry,[7,8] spectrofluorimetry,[9,10] thin layer chromatography (TLC)-fluorescence spectrodensitometry,[11,12] capillary electrophoresis,[13,14] and flow-injection chemiluminescence[15,16] are several methods used for ofloxacin determination. Some of these methods are expensive, elaborate, and often not sensitive enough to directly determine trace amounts of ofloxacin in urine samples.

Methods

Results

Conclusion