Validation of liquid-liquid extraction followed by flow-injection negativeion electrospray mass spectrometry assay to topiramate in human plasma

This paper describes the development and validation of a method for the qua ntitative analysis of Topiramate (2,3:4,5-bis-O-(1-methylethylidene)-beta - D-fructopyranose sulfa mate), a new antiepileptic drug, in human plasma usi ng liquid-liquid extraction followed by flow-injection negative ion electro spray mass spectrometry. Using Prednisone (1,4-pregnadiene-17-alpha ,21-dio l-3,11,20-trione [10 mug/mL]) as an internal standard, calibration curves f or Topiramate were linear over a range of 1 to 30 mug/mL in human plasma an d were highly reliable (r(2) = 0.9991). The lower limit of quantitation of the assay was 2 mug/mL in human plasma. Precision (%CV <15%) and accuracy ( <20%) for both intra- and inter-day validations were satisfactory. The meth od has been used in clinical pharmacology research. Copyright (C) 2001 John Wiley & Sons, Ltd.