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Forensic
Applications
Cocaine and Benzoylecgonine in Urine, Blood, Plasma/Serum and
Tissue for GC or GC/MS Confirmations
Using 200mg 10mL HyperSep Verify-CX Extraction Column
(Part Number: 60108-742)
Prepare Sample
To 1mL of 100mM phosphate buffer (pH 6.0) add
internal standards*
Add 2mL of urine, blood, plasma/serum or 1g (1:4) of
tissue homogenate
Mix/vortex
Add 2mL of 100mM phosphate buffer (pH 6.0)
Mix/vortex
Sample pH should be 6.0±0.5
Adjust pH accordingly with 100mM monobasic or dibasic
sodium phosphate
Centrifuge as appropriate
Condition Verify-CX Extraction Column
3mL of CH
3
OH then aspirate
3mL of DI H
2
O then aspirate
1mL of 100mM phosphate buffer (pH 6.0) then aspirate
NOTE:
Aspirate at <3"Hg to prevent sorbent drying
Apply Sample
Load sample at 1 to 2mL/minute
Wash Column
3mL of DI H
2
O
2mL of 100mM HCl
3mL of CH
3
OH
Dry column (5 minutes at >10"Hg)
Elute Cocaine and Benzoylecgonine
3mL of CH
2
Cl
2
/IPA/NH
4
OH (78:20:2)
Collect eluate at 1 to 2mL/min
NOTE:
Prepare elution solvent fresh daily; add IPA/NH
4
OH mix,
then add CH
2
Cl
2
(pH 11-12)
Dry Eluate
Evaporate to dryness at <40°C
Derivatize
Add 50µL ethyl acetate and 50µL BSTFA
(with 1% TMCS)***
Overlay with N
2
and cap
Mix/vortex
React for 20 minutes at 70°C
Remove from heat source to cool
NOTE:
Do not evaporate BSTFA solution
Quantitate
Inject 1 to 2µL onto gas chromatograph
For mass spectrometry, monitor the following ions (GC/MS):
Compound
Primary Ion** Secondary
Tertiary
D
3
-cocaine*
185
201
306
Cocaine
182
198
303
D
3
-benzoylecgonine-TMS*
243
259
364
Benzoylecgonine-TMS
240
256
361
* Suggested internal standards
** Quantitation ion
*** 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