Chaitanya Sucharitha Kolakaluri, Anusha Goli, G. Saravanan. D. Visaga Perumal

Abstract

Present study reports the development and validation of Metaxalone in human plasma by LC-MS/MS using electron spray ionization technique. Metaxalone-d6 was used as internal standard. The chromatographic separation of analyte and internal standard was achieved by using ACE 5μ C18, 100 X 4.6 mm column as stationary phase and 10 mM Ammonium Acetate: Methanol with Acetonitrile (60:40) as mobile phase at a flow-rate of 1 ml/min. MS detection was performed at transitions of m/z 222.100/161.200 and 228.200/167.200 in multiple reaction monitoring for Metaxalone and Metaxalone-d6 at positive mode. Metaxalone was extracted from the plasma by liquid-liquid extraction using 0.2M NaOH as treatment buffer and Ethyl acetate as extraction solvent. The present method was found to be linear over the concentration range of 25.006 - 12059.526 ng/ml (r2-0.9983). The limit of quantification of Metaxalone in plasma was found to be 25.006ng/ml. The retention times of Metaxalone and Metaxalone-d6 were found to be 2.01 min and 1.98 min, respectively. The analyte was found to be stable under various stability tests such as freeze-thaw, bench top, wet extract, dry extract, auto sampler and interim studies. This simple, rapid and specific validated method was successfully applied for the faster analysis of Metaxalone in human plasma in bioavailability and bioequivalence studies.