84 / 144
84
Forensic
Applications
Cocaine and Benzoylecgonine in Oral Fluid for GC/MS Confirmation
Using 50mg 1mL HyperSep Verify-CX Extraction Column
(Part Number: 60108-741)
Prepare Sample
Add 100 to 500µL of neat oral fluid sample to a clean
test tube
Add internal standard(s) and let sit for 10 minutes at
room temperature
Add 800µL of 100mM phosphate buffer (pH 6.0)
Mix/vortex for 10 seconds (Sample pH should be 6.0±0.5)
Adjust pH accordingly with 100mM monobasic or dibasic
sodium phosphate
Condition Verify-CX Extraction Column
200µL of CH
3
OH
200µL of DI H
2
O
200µL of 0.1N HCl
Apply Sample
Load sample at 1mL/minute (do not exceed this flow rate)
Wash Column
500µL of DI H
2
O
500µL of 100mM HCl
500µL of CH
3
OH/DI H
2
O (50:50)
Dry column (5 minutes at >10"Hg)
Elute Compounds
800µL of CH
2
Cl
2
/IPA/NH
4
OH (70:26:4)
Collect eluate at 1mL/min (do not exceed this rate)
NOTE:
Prepare elution solvent fresh daily; add IPA/NH
4
OH mix,
then add CH
2
Cl
2
(pH 11-12)
Concentrate Eluate
Evaporate to full dryness at <40°C under a stream of
nitrogen
Derivatize
Fluoroalkylate*:
Add 100µL PFPA (PFAA)**
Overlay with nitrogen and cap
React for 20 minutes at 70°C
Evaporate to dryness at <40°C
Reconstitute with 50µL ethyl acetate
TMS*:
Add 25µL of BSTFA (with 1% TMCS)*** and
25µL of ethyl acetate
Overlay with nitrogen and cap
Mix/vortex then react for 30 minutes at 70°C
Remove from heat and allow to cool
NOTE:
Do not evaporate BSTFA solution
Quantitate
Inject 2µL onto gas chromatograph
For mass spectrometry, monitor the following ions:
Analyte
Target (Quantitation) Ion Qualifier Ions
Cocaine
182
198, 303
Cocaine-D3*
185
201, 306
Benzoylecgonine
240
256, 361
Benzoylecgonine-D8-TMS*
243
259, 369
* Alternative derivatizations may be used
** Part number TS-65193 (10 x 1mL ampules)
*** Part number TS-38831 (10 x 1mL ampules)
Recommended GC Columns
Part Number
TRACE TR-DoA5 Column, 15m x 0.25mm x 0.25µm
26AF130P
TRACE TR-DoA35 Column, 15m x 0.20mm x 0.33µm
26AC497P