Ultra-performance liquid chromatography coupled to electrospray ionization-tandem mass spectrometric method for simultaneous determination of acemetacin in presence of its metabolite indomethacin and degradation products

Abstract

Selective and sensitive ultra-performance liquid chromatography-tandem mass spectrometric technique (UPLC-MS/MS) was investigated for simultaneous determination of acemetacin (ACM) in presence of its metabolite (indomethacin) and degradation products in 3 min run time. The column employed was a Hypersil gold 50 mm × 2.1 mm (1.9 μm) with an isocratic mobile phase consisted of 0.1% formic acid aqueous solution and acetonitrile (10:90, v:v)  with flow rate 250 µL/min. Detection of the cited drug was carried out using multiple reaction monitoring (MRM) mode on a triple quadrupole mass spectrometer coupled with electrospray ionization (ESI) m/z 416.44 → 139.24 for ACM and m/z 256.31 → 167.00 for diphenhydramine internal standard. Various parameters were studied; mobile phase composition, flow rate, rate of fragmentation, rate of collision and mode of ionization. Good linear relationship was obtained in concentration range 8.0-500.0 ng/mL (r = 0.9994). The method was validated (linearity, range, precision, accuracy, limit of quantification and limit of detection) according to ICH guidelines and there is no significance difference between the proposed method and the reference HPLC method regarding accuracy and precision. The simplicity and sensitivity of this method allows its use as stability indicating method.