Abstract

A VALIDATED LCMS/MS METHOD FOR ESTIMATION OF CINACALCET IN HUMAN PLASMA

Srinivasa Reddy, Imran Ahmed. M, Licto Thomas, Nirmala Nayak, Arindam  Mukhopadhyay* and Saral Thangam

Abstract

The calcium-sensing receptor (CaR) is responsible for controlling the synthesis and secretion of parathyroid hormone. Cinacalcet, an allosteric modulator of CaR signaling, is used for the treatment of secondary hyperthyroidism in patients with chronic kidney disease and for the treatment of elevated calcium levels in patients with parathyroid carcinoma. A highly sensitive LCMS/MS method for quantification of cinacalcet was developed and validated. An isocratic binary mobile phase containing 5mM Ammonium acetate (pH 4.0±0.2): Acetonitrile:: 40:60 (v/v) was used at a flow rate of 1.2 ml/min to achieve chromatographic separation of cinacalcet on SCX column (50 x 4.6 mm; 5 μm) maintained at 50 0C. It is estimated in API 4000 Mass spectrometer in the positive atmospheric pressure ionization mode by following multiple reactions monitoring (MRM) transitions for parent and daughter ions. A linear calibration plot was achieved for cinacalcet in the concentration ranges 0.207 to 120.507 ng/ml. The mean percentage of recovery was 108 with mean % CV of 2.10. It is a fully validated method and can successfully be applied for estimation of cinacalcet during bio-studies.

Keywords: Cinacalcet, Liquid Chromatogrphy – mass spectrometry (LCMS/MS), Ionexchange (SCX) column, Human Plasma, Calcium – sensing receptor, Parathyroid hormone.