Validation of the Method of Identification and Quantitative Determination of Bacitracin in the Form of Bacitracin Derivative with Dabsyl Chloride by Thin-Layer Chromatography and Densitometry

摘要

A thin-layer chromatographic (TLC)-densitometric method has been developed for identification and quantitative determination of bacitracin derivative with dabsyl chloride. The analysis of antibiotic was achieved on the silica gel TLC plates with fluorescent indicator with H-butanol-2-butanone-25% ammonia-water (10:5:2:2, v/v) as mobile phase. The densitometric measurements were made at 460 nm. Under these conditions, good separation of chosen polypep-tide antibiotic from reagent used to make a complex was obtained.The method distinguishes of high sensitivity, LOD from 8.6 ng per band and LOQ from 26.2 ng per band, wide linearity range from 0.0854 to 0.8536 ug per band for bacitracin. The precision of the method was good; relative standard deviation (RSD) varied from 1.23% to 2.47%. Satisfactory results of validation of the method were also confirmed by determination of selected antibiotic in pharmaceutical commercial preparations. The results obtained by TLC-densitometric method were compared with those obtained by spectrophotometric method.