Validated spectrofluorimetric method for quantification of pentazocine in human serum

A protein precipitation method was developed and optimized for extraction of pentazocine from human serum, and subsequently a direct spectrofluorimetric method was developed and validated for the determination of the extracted drug. The extraction efficiency of the precipitation method employing TCA (10%) and dioxan was excellent (95-102%). The working conditions of spectrofluorimeter were optimized for accurate and sensitive quantification of the drug by varying slit widths and instrumental sensitivities. The excitation and emission wavelength were found to be 284 and 311 nm respectively. The method was found sensitive (LOQ and LOD being 0.025 and 0.01 ppm, respectively) and linear in the concentration range of 0.025 n 2.5 ppm (with correlation coefficient 0.9999). The method was sufficiently precise (% RSD 95% with % RSD of 1 at each concentration indicating the method to be sufficiently accurate. The method can be employed for the quantification of pentazocine in human serum for pharmacokinetic studies.