Evaluation of microextraction by packed sorbent and micro-liquid chromatography-tandem mass spectrometry as a green approach in bioanalysis.

In this study the use of micro-liquid chromatography coupled to tandem mass spectrometry (μLC-MS/MS) was investigated in routine bioanalysis application for separation and quantification of pro-drug AZD6319 (developed for aldezheimer treatment). Microextraction by packed sorbent (MEPS) was used as sample clean-up method. The focus of this study was put on the evaluation of the usability of smaller column diameters such as 1.0 and 0.3 mm instead of 2.1 mm in bioanalysis application to reduce solvent consumption and sample volumes. Solvent consumption was reduced by 80% when a 1.0 mm column was used compared with 2.1 mm column. Robustness of the micro-columns in terms of accuracy and precision was investigated. The application of μLC-MS/MS for the quantitative analysis of AZD6319 in plasma samples showed good selectivity, accuracy and precision. The coefficients of determination (R(2) ) were >0.998 for all runs using plasma samples on the studied micro-columns. The inter-day accuracy values for quality control samples ranged from 99 to 103% and from 96 to 105% for 0.3 × 50 mm and 1.0 × 50 mm columns, respectively. The inter-day precision values ranged from 4.0 to 9.0% and from 4.0 to 8.0% for 0.3 × 50 and 1.0 × 50 mm columns, respectively. In addition the sensitivity was increased by three times using a 1.0 mm column compared with 2.1 mm. Furthermore, robustness of the micro-columns from different manufacturers was investigated.