DETERMINATION OF THE RELATIVE AMOUNTS OF THE B-COMPONENT AND C-COMPONENT OF NEOMYCIN BY THIN-LAYER CHROMATOGRAPHY USING FLUORESCENCE DETECTION

The determination of the relative amounts of the B and C components of neomycin sulphate by thin-layer chromatography using silica gel plate s from Whatman as the stationary phase is described. The mobile phase consisted of methanol-20% (m/v) sodium chloride solution (15:85). Fluo rescence detection was performed after derivatization with 4-chloro-7- nitrobenzo-2-oxa-1,3-diazole. The influence of different parameters on the separation was investigated. A number of commercial samples was a nalysed using this method and the results were compared with results o btained with ion-exchange chromatography and ninhydrin colorimetric de tection, which is the official method prescribed by the European Pharm acopoeia. The described method is much easier to perform than the offi cial method.