HIGH-THROUGHPUT LIQUID-CHROMATOGRAPHY MASS-SPECTROMETRY BIOANALYSIS USING 96-WELL DISK SOLID-PHASE EXTRACTION PLATE FOR THE SAMPLE PREPARATION

The 96 well solid phase extraction (SPE) operated by robot in the LC/M S/MS bioanalysis offered rapid sample preparation for drugs and metabo lites in biological matrices, based on simultaneous extraction of 96 s amples. The use of a disk as sorbent in the 96 well plate further impr oved the performance of SPE and allowed for small elution volumes, mak ing it possible to 'dilute and shoot' after SPE elution. In this study , a 96 well plate (Empore(TM)) was developed, characterized and optimi zed for several pharmaceutical compounds. In addition, a robot (MultiP robe(TM)) was modified to automate the 96 well plate operation. Exampl es were given to illustrate the major differences of using 96 well dis k plate SPE in the method development as compared to the traditional S PE. This technology has been successfully used to support many clinica l studies, Typically, a batch of 96 samples were prepared in 1-1.5 hou rs unattended (except for the replacement of a collection plate). Cons iderable savings in disposable supplies were also noted. (C) 1998 John Wiley & Sons, Ltd.