Bio-analytically fluorimetric method for estimation of ertapenem in real human plasma and commercial samples; application to pharmacokinetics study

Ertapenem (EPM) has been recently approved by the United States Food and Drug Administration (US-FDA) as an antimicrobial drug. EPM has a broad spectrum of action against different bacterial strains and is most commonly prescribed in Egypt for the treatment of Klebsiella pneumonia. In this study, EPM was estimated using a sensitive and selective spectrofluorimetric method for human plasma and pharmaceutical vials. The measured fluorescence (at 540 nm) was obtained from reaction of EPM with 0.05% w/v benzofurazan (NBD-Cl) using 0.1 M borate buffer pH 8.8 after excitation at 460 nm. The fluorometric linear range was stable from 10 to 350 ng ml⁻¹. The lower limit of detection and the lower limit of quantitation were found to be 2.13 and 6.47 ng ml⁻¹ respectively. Many factors such as pH, temperature, heating time, and NBD-Cl concentration were optimized. The presented work was validated according to International Council for Harmonisation guidelines and bio-analytically validated using FDA recommendations. The significant finding of this study, sensitivity, was successfully applied in Egypt for a pharmacokinetic application and commercial vials. Pharmacokinetic parameters were studied and the result, recorded as C_max of EPM, was found to be 83.60 μg ml⁻¹ after infusion of 0.5 g of Invanz® for 30 min. AUC_0-∞ was found to be 320 ± 30.2 μ.h ml⁻¹.