DETERMINATION OF CLAVAM-2-CARBOXYLATE IN CLAVULANATE POTASSIUM AND TABLET MATERIAL BY LIQUID-CHROMATOGRAPHY TANDEM MASS-SPECTROMETRY

A liquid chromatography-thermospray tandem mass spectrometric (LC-MS-M S) method was developed to determine the presence of clavam-2-carboxyl ate in clavulanate potassium at below the 0.01% level stated in the US Pharmacopeia (USP). The USP method is for bull; chemical but it was h oped to extend the determination to formulated products. The method de scribed here involves selected reaction monitoring of m/z 156 giving r ise to m/z 114, using negative ion thermospray ionisation. The selecte d reaction monitoring method was highly specific for clavam-2-carboxyl ate and was capable of detecting clavam-2-carboxylate in clavulanate p otassium at levels of 0.001% (w/w), an order of magnitude better than the sensitivity required by the USP.