Noor Shabana, K Dayananda Reddy
A sensitive and selective liquid chromatographic-tandem mass spectrometric (LC/MS/MS) method was developed and validated for the trace analysis (>1 ppm level) of p-Toluenesulfonicacid, a genotoxic impurity, in acyclovir drug substances. The chromatographic separation was achieved on Symmetry C-18 (150 X 4.6mm, 3.5μm) column using a mobile phase consisting of 5 mM ammonium acetate and methanol (70:30 v/v) at flow rate of 0.4 mL /min. The API-4000 LC/MS/MS was operated on an electrospray in negative mode. The selected ion monitoring (SIM) mode was used during the analytical run and it is able to quantitate up to 1.5 ppm of p-Toluenesulfonicacid. The newly developed method was validated as per achieved on International Conference on Harmonization (ICH) guidelines