Analysis of Drugs of Abuse using Automated Disposable Pipette Extraction and LC/MS/MS


App Note 7/2009

This study focuses on the automated extraction of small sample volumes coupled to LC/MS/MS in order to provide high throughput analysis of an extended list of benzodiazepines. Using a GERSTEL MPS autosampler, DPX extractions of a variety of biological matrices were performed, using a mixed-mode cation exchange (DPX-CX) sorbent. The resulting eluents from the automated DPX extractions were then introduced into an Agilent 6410 LC/MS/MS instrument. Coupling DPX to LC/MS/MS provides rapid, just-in-time sample preparation for high throughput analysis. Data show the use of an Agilent 6410 LC/MS/MS instrument to be a highly sensitive procedure for the analysis of benzodiazepines with limits of quantitation of 0.5 ng/mL, and good linearity. The DPX extraction removes potential matrix interferences and ion suppression, and high sensitivity is therefore achieved.