Solid phase extraction liquid chromatography mass spectrometry method with electrospray ionization for the determination of Ondansetron in human plasma: Development and validation consideration

Abstract

A new liquid chromatography mass spectrometry method with electrospray ionization was developed for the estimation of Ondansetron in human plasma. Sample preparation was carried out by solid-phase extraction that enabled direct injection into the LC–MS/MS system. Ondansetron and an internal standard (ISTD), Ramosetron, were separated by using a Gemini NX C18 analytical column (100×4.6mm i.d., particle size 5μm) with isocratic elution. The mobile phase was composed of a mixture of ammonium formate buffer (pH 3.0; 2mM) and acetonitrile (30:70, v/v), pumped at a flow rate of 0.5mL/min. Quantitation of the analyte was performed with multiple ion monitoring (MRM) in positive ionization mode using electrospray ionization interface. The ion transitions recorded were m/z 294.3/170.0 for Ondansetron and m/z 280.3/121.3 for ISTD. The method was validated over a wide dynamic concentration range of 1.00–100.00ng/mL (r⩾0.9996). The lower limit of quantitation (LLOQ) was 1.00ng/mL. The extraction recovery was above 81.50% for analyte and above 85.33% for ISTD. A run time of less than 3.0min for each sample made it possible to analyze a large number of human plasma samples per day. The proposed method was successfully applied for determination of Ondansetron in bioequivalence study of 4 or 8mg Ondansetron tablet.