MICROCOLUMN LIQUID-CHROMATOGRAPHY COUPLED WITH SOLID-PHASE MICRO EXTRACTION (SPME MICRO-LC) FOR THE ANALYSIS OF BENZODIAZEPINES IN HUMAN URINE/

The interface technique between SPME and micro-LC has been evaluated f or benzodiazepines analysis in human urine, Three SPME fiber coatings such as polyacrylate (PA), carbowax/template (CW/TEP) and sol-gel C-11 polydimethylsiloxane (PDMS) were compared in the performance for SPME process such as extraction efficiency, extraction time and total anal ysis time required. As the results using the CW/TEP fiber for SPME and 1.0 mm i.d, LC column as the separation medium the analysis of benzod iazepines in patient's urine can be performed in 2 hours with very low solvent consumption less than 1.5 mL solvents in whole analytical pro cedures.