Modeling and optimization of a novel RP-UPLC and MCR spectrophotometric methods for simultaneous determination of five cephalosporins in spiked human plasma: Application to lean six sigma thinking hats and antimicrobial activity

摘要

Novel, rapid, simple and sensitive RP-UPLC and spectrophotometric methods were optimized and validated for simultaneous determination and separation of Cephalexin (CPH), Cefaclor (CFC), Cefixime (CFX) and Cefdinir (CFR) in pharmaceutical dosage forms using Ceftazidime (CFZ) as internal standard spiked with human plasma and application to lean six sigma methodologies and antimicrobial activity. Mixing 0.5mL of the Innovative enzyme Lactamator (TM) with the cephalosporin drug and holding the sample for 1.5 h for deactivation of cephalosporin molecule's antibacterial properties. Isocratic chromatographic system was performed at ambient temperature using mobile phase consisting of acetonitrile: 40% tetrabutylammonium hydroxide adjusted to pH 7.0 +/- 0.1 with 10% phosphoric acid (72.5,27.5, v/v) on Waters CORTECS (R) C18 column (50 mm x 4.6 mm, 2.7 mu m particle size) at a flow rate of 0.25 mL/min, injection volume 0.3 mu L for RP-UPLC and UV detection at 265 nm with total run time less than 8 min for the mixture. Plasma samples were deprotonated using a mixture of methanol: acetonitrile (90, 10). The method has been validated in terms of linearity, specificity, lower limit of quantification (LLOQ), freezing stability, bench - top stability and real time. Relative standard deviation values (RSD) were < 15.0% regarding the intra-inter day precision and accuracy of low, medium and high concentration of quality control sample. Mean centering of the ratio spectra (MCR) spectrophotometric method was successfully applied for resolving spectral overlap of drugs at 265.9 nm, 271.95 nm, 285.2 nm, 249.2 nm and 236.4 nm for CPH, CFC, CFR, CFX, and CFZ, respectively. Lean six sigma methods were used for identifying and evaluating the effects of potential causes of failure that could occur in project plans or processes, reduce or eliminate non- value-added activities, develop contingencies for each problem related to fault tree analysis and failure modes and effects analysis.