•
5
•
2005vol. 2
Figure3
Distinctivemass fragments ensurepositive identification
of lidocaineand caffeine.
Figure4
Pinnacle II™Amino columnprovides fast, reliableanalyses
for sugars.
positive identificationandallowedquantificationof
each compound. Lidocaine and caffeine have dis-
tinctive mass fragments of 86m/z and 194m/z,
respectively (Figure3).
HPLC
Sugars are not easily volatilized and, therefore, are
difficult toanalyzebyGC,makingHPLC thebetter
chromatographic approach for this analysis.
Further, refractive index (RI) or evaporative light-
scattering (ELS) detection must be used because
sugars have no UV chromophore. HPLC/RI or
HPLC/ELS provides reproducible retention times,
adequate peak identification and good quantifica-
tion for sugars, as shown inFigure4.
HPLC/MS methods for simultaneous analysis of
cocaine, sugars,andotherclassesof adulterantsand
diluents have not yet been developed, but such
methods would enable analysts to evaluate street
cocainemixtures inone analysis.Columnparame-
ters andmobile phase compositionwill be critical
parameters tooptimize.
Conclusions
Cocaine samplescanbe“fingerprinted”by identify-
ing and quantifying the adulterants and diluents
mixed with the drug. GC/MS provides adequate
quantitative information about the concentration
of each additive, relative to the cocaine concentra-
tion, and provides undisputable identification of a
substance(retention timeandmassspectrumdata).
Therefore,GC/MS is thepreferredchromatograph-
icmethod for analyzing cocaine andmost cocaine
adulterants. Sugars arebest analyzedbyHPLC.
formore information
Smith, F.P,
Handbook of ForensicDrugAnalysis
, pp.235-275,
Elsevier, 2005.
Telepchak, M.J.,T.F. August, andG. Chaney,
Forensic andClinical
Applications of SolidPhase Extraction
, pp.204-213, Humana
Press, 2004.
Pinnacle II™Amino
3µmParticles, 4.6mm ID
cat.#
price
150mm
9217365
$284
Rtx®-440 (fusedsilica)
(proprietary intermediate-polarity Crossbond
®
phase)
ID df (µm)
temp. limits
length cat.#
price
0.25mm 0.25 20°C to 320/340°C 30-Meter 12923
$445
0.25mm 0.50 20°C to 320/340°C 30-Meter 12938
$445
Peak List:
Conc. (mg/mL)
1. fructose
2.0
2. glucose
2.1
3. sucrose
4.0
4. maltose
4.5
5. lactose
4.4
LC_0223
Column:
Pinnacle II
™
Amino
Cat.#:
9217365
Dimensions:
150 x 4.6mm
Particle size:
3µm
Pore size:
110Å
Conditions:
Mobile phase: water:acetonitrile (25:75, v/v)
Flow:
1.5mL/min.
Temp.:
35°C
Det.:
refractive index@35°C
Sample:
Inj.:
5µL
Solvent:
mobile phase
glucose
2.0mg
fructose
2.1
lactose
4.4
maltose
4.5
sucrose
4.0
No data pack available.
CarbohydrateHPLCPerformanceCheckMix
Dry components in 4mL screw-cap vial.
Reconstitute in 1mL acetonitrile:water (75:25) to 2.0, 2.1, 4.4, 4.5,
4.0mg/mL, respectively.
cat.# 31809 (ea.)
$30
tech
tip
We recommend using anHPLC guard column for this application.
ForTrident
™
guard column systems, refer to our catalog, or visit
ourwebsite at
Column:
Rtx
®
-440 30m, 0.25mm ID, 0.50µm (cat.# 12938)
Sample:
100µg/mL each compound inmethanol
Inj.:
1.0µL split (split ratio 1:10), laminar cup splitter inlet liner (cat.# 20801)
Inj. temp.:
250°C
Carrier gas:
helium, constant flow
Flow rate:
1mL/min.
Oven temp.:
150°C to 275°C@ 25°C/min., to 300°C@ 15°C/min. (hold 5.0min.)
Det.:
MS
Transfer line temp.: 180°C
Scan range:
35-550amu
Ionization:
EI
Mode:
scan
Lidocane
Caffeine
