| abstract Daptomycin (DPT) was the first lipopeptide antibiotic available for commercialization. It is active against gram-positive bacteria, including resistant strains. This work aimed to develop and validate a turbidimetric microbiologic assay to determine daptomycin in an injectable form. A 3x3 design was employed, at concentrations of 1, 2 and 4.0 µg/mL. The microorganism test used was Staphylococcus aureus ATCC 6538p, and Antibiotic Medium 3 was used as the culture medium. Method validation demonstrated that the bioassay was linear (r=0.9995), precise (RSD=2.58%), accurate (recovery 100.48± 2.11%), and robust. Degradation kinetics was also performed in an alkaline medium, indicating that daptomycin degradation follows first order kinetics under these... |
