Moving from fast to ballistic gradient in liquid chromatography/tandem mass spectrometry pharmaceutical bioanalysis: matrix effect and chromatographic evaluations

Abstract

The paper describes the steps taken by the authors to move from a fast to a ballistic gradient in routine liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis of plasma samples from pharmacokinetic (PK) profiling of new chemical entities. The reduction of column dimensions from 50 T 4.6 mm to 30 T 2.1 mm followed by optimization of chromatographic separation led to a decrease in the typical runtime from 5 (fast) to 2 min (ballistic) using an API4000 tandem mass spectrometer in Turbo Ionspray mode for detection. Three analytical standards representing typical molecular structures from our sample repository were used to spike plasma from four different species (rat, dog, human and mouse). Two different approaches were used to evaluate matrix effect: post-column infusion and comparison of the peak areas of neat standards and standards spiked after extraction into different pools of plasma; the influence of PEG400 as a typical dosing vehicle was also considered. Two different protein precipitation procedures were taken into account for sample extraction prior to injection. Peak shape, width and height, selectivity and sensitivity of the method were taken into account for chromatographic evaluation. The ballistic method was successfully crossvalidated with the conventional fast gradient chromatographic assay.

Accelerating high quality bioanalytical LC/MS/MS assays using fused-core columns

“…These include using sub-2 m particle columns [1,2], ballistic gradients [3,4], fast isocratic LC/MS runs [5], increased flow rates using shorter columns [6], and the use of monolithic [7] or fused-core [8][9][10][11][12] HPLC columns. With the recent advent of direct atmospheric pressure sampling techniques for MS, various groups have also explored assays that may require little or no sample preparation, and introduce samples to the MS with no chromatography, using methods such as DESI [13,14] and DART [15,16].…”

Development of a sensitive UPLC-ESI-MS/MS method for quantification of sofosbuvir and its metabolite, GS-331007, in human plasma: Application to a bioequivalence study

“…Finally, the best 284 chromatographic conditions were achieved using an isocratic mode of acetonitrile: 285 0.1% formic acid (50:50, v/v) at a flow rate of 0.3 ml/min. Increased lifetime of 286 smaller columns, reduction of instrument time and less eluent consumption together 287with a cleaner mass source thanks to a smaller injection volume make this analytical 288 approach even more attractive[10]. All the analytes and IS are eluted in the narrow 289 range of retention times (0.30-0.67 min.)…”

A rapid and sensitive method for the quantitation of montelukast in sheep plasma using liquid chromatography/tandem mass spectrometry

“…In order to achieve ultra-fast run times, the use of a 'ballistic' gradient was required in combination with high flow-rate and a short column. This type of approach has been reported by several authors [9,10] and was successfully applied herein.…”