A simple, rapid and specific method for measurement of topiramate in human plasma by LC-MS/MS employing automated solid-phase extraction techniques: Application for bioequivalence study

Abstract

A rapid liquid chromatography coupled with ESI tandem mass spectrometry (LC-MS/MS) method was developed and validated for the quantification of topiramate in heparinized human plasma. The plasma samples were prepared by solid-phase extraction (SPE) method without drying and then reconstitution. Topiramate and the topiramate d-12 internal standard (IS) were chromatographed on a Betasil C18 column at a flow rate of 0.5 mL/min. The total run time was 1.80 min. An ESI interface with negative ion mode was selected for ionization of analyte and IS. The mass transition [M-H] ions used for detection were m/z 338.10→78.20 for topiramate, m/z 350.40→90.10 for IS. The method was linear in the concentration range of 10-4200 ng/mL with r≥0.9992. Recovery of topiramate and IS ranged from 78.20 to 87.74%. The validated method has been successfully used to analyze human plasma samples for application in 100 mg fasted and fed pharmacokinetic studies.

Liquid chromatography tandem mass spectrometry method for quantification of topiramate in human plasma

“…A mixture of methyl-t-butyl ether and hexane at 19:1 (v/v) produced the highest recovery. The developed method was straightforward and utilized less solvent compared to other reports 7,8,10,11 .…”

“…Although, several LC-MS/MS methods for determination of topiramate in human plasma have been reported, there are some analytical limitations such as the need for large volume of plasma samples, timeconsuming and complicated sample preparation method, high injection volumes, low sensitivity and narrow linearity range (10-2000 ng/mL) [6][7][8][9][10][11] .…”

Simple and sensitive high performance liquid chromatography method with fluorescence detection for therapeutic drug monitoring of topiramate

“…For various reasons, including insufficient analytical sensitivity 12,23,24,26,28,29,31,35 and linearity, 24,25,[32][33][34]36 previously reported liquid chromatography techniques coupled with various detection systems can not accurately determine full therapeutic range of TPM concentrations. These methods either lack adequate sensitivity, and consequently cannot be applied in pharmacokinetic studies, or the method range is to narrow and therefore they are not practical for routine TDM.…”

“…It needs to be emphasized that sensitivity of the present HPLC-FLD method is comparable to the sensitivity of the more sophisticated LC-MS methods, 30,[32][33][34]36 which makes it appropriate also for pharmacokinetic profiling and bioequivalence assessments of low-dose TPM formulations in healthy volunteers.…”

“…15 Various analytical methods have been reported for measurement of TPM in biological fluids, including immunoassays, 16,17 gas chromatography (GC) coupled to flame ionization detection (FID) 18 or nitrogen phosphorous detection (NPD), [19][20][21][22] high performance liquid chromatography with UV (HPLC-UV) 23 or fluorescence detection (HPLC-FLD), [24][25][26] capillary electrophoresis with UV detection, 27 liquid chromatography coupled to mass spectrometry (LC-MS), 28,29 and more recently, liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). 12,[30][31][32][33][34][35][36] The analysis of TPM in biological fluids is complicated, because like most other carbohydrates and their derivatives, TPM does not contain any chromophores that absorb above 190 nm. Consequently, TPM has extremely low UV-visible absorbance and no spontaneous fluorescence, and cannot be directly analyzed by conventional HPLC with UV or fluorescence detection.…”