Journal of Bioequivalence & Bioavailability

A novel method for the quantification of Lamotrigine in human plasma using UPLC with tandem mass spectrometry

3^rd World Congress Bioavailability & Bioequivalence

March 26-28, 2012 Marriott Hotel & Convention Centre, Hyderabad, India

Anju Aji , Sarita Karthikeyan, Sarabjit Singh and Shivanand Puthli

Posters: J Bioequiv Availab

Abstract:

Introduction: Lamotrigine is an anticonvulsant drug used in the treatment of epilepsy and bipolar disorder. A novel high performance liquid chromatography positive ion electrospray ionization tandem mass spectrometry method was developed and validated for the quantification of Lamotrigine in human plasma. Method: The plasma sample was precipitated using acid and subsequently extracted using liquid-liquid extraction. The analyte was separated using an isocratic mobile phase on a reverse phase UPLC column to meet the demands of the clinical laboratory for speed of analysis and chromatographic resolution. Detection was carried out by MS/MS in the multiple reaction monitoring mode using the respective (M+H)+ ions, m/z 255.9 → 255.9 and m/z 261.9 →261.9 for the internal standard. The parent ion was monitored in the MRM mode with negligible collision energy as the product ions were not sensitive enough for detection. The developed method was validated as per the US FDA guidelines for bioanalytical method validation (May2001). Results: The assay exhibited a linear dynamic range of 4-2000 ng/ml for Lamotrigine in human plasma. The lower limit of quantification was 4 ng/ml with a relative standard deviation of less than 9.2 %. No interference by endogenous substances or matrix effect was observed. The intra-day and inter-day accuracy and precision (%CV) values were in the range of 98.1-105.7% and 1.44-14.6% respectively. The spiked plasma samples were found to be stable at ambient temperature for 5 hrs, after long-term storage at -80?C for 93 days, and after 3 freeze-thaw cycles. The processed plasma samples were found to be stable in autosampler for 48hrs at 5?C. A very short run time (2min) for each sample made it a high throughput method for estimation of clinical samples. Thus the developed and validated method for estimation of Lamotrigine in human plasma could be successfully used to evaluate plasma concentration profiles in human subjects.