Methods for impurity profiling of heroin and cocaine

68

Methods for impurity profiling of heroin and cocaine

Figure IV.

Typical capillary gas chromatogram of (trace) impurity compounds

detected after extraction from a sample of heroin of Southwest Asian origin 

using methodology similar to that of method B1

a

Source: Reprinted from Forensic Science International, vol. 114, No. 2, L. Strömberg and others,

“Heroin impurity profiling: a harmonization study for retrospective comparisons”, pp. 67-88, Copyright

2000, with permission from Elsevier.

a

For details on peak identification, see table 3.

Peaks:

1 = Meconine

3 = Unknown

4 = 3,6-Dimethoxy-4,5-epoxyphenanthrene

5 = 4-O-Thebaol 

7 = 4-O-Acetylthebaol

9 = 4,6-Diacetoxy-3-methoxyphenanthrene

10 = Unknown

11 = 6-O,N-Diacetylnorcodeine

12 = Unknown

14 = 4-Acetoxy-3,6-dimethoxy-5-[2-(N-

methyl-acetamido)]ethylphenanthrene

15 = 3-O,6-O,N-Triacetylmorphine

16 = N-Acetylnorlaudanosine

18 = Unknown

19 = 4-Acetoxy-3,6-dimethoxy-8-[2-(N-

methyl-acetamido)]ethylphenanthrene

20 = N-Acetylnornarcotine

21 = (E)-N-Acetylanhydronornarceine

22 = (1R,9S)-1-Acetoxy-N-acetyl-1,9-

dihydroanhydronornarceine

23 = (Z)-N-Acetylanhydronornarceine

IS (C40) = n-Tetracontane (internal stan-

dard)

---

Annex III

69

Table 3.

Identification of peaks in the capillary 

gas chromatogram in figure IV

Peak

Identification

Molecular Base 

Relative 

Retention 

weight

peak

retention

index

time

a

1

Meconine

194

165

0.152

1765

3

Unknown

204

0.364

2290

4

3,6-Dimethoxy-4,5-epoxyphenanthrene

252

237

0.383

2333

5

4-O-Thebaol

254

254

0.465

2522

7

4-O-Acetylthebaol

296

254

0.494

2591

9

4,6-Diacetoxy-3-methoxyphenanthrene

324

240

0.542

2708

10

Unknown

252

0.634

2944

11

6-O,N-Diacetylnorcodeine

369

87

0.646

2977

12

Unknown

254

0.653

2995

14

4-Acetoxy-3,6-dimethoxy-5-

[2-(N-methylacetamido)]ethylphenanthrene

395

265

0.677

3064

15

3-O,6-O,N-Triacetylmorphine

397

87

0.690

3100

16

N-Acetylnorlaudanosine

385

234

0.707

3147

18

Unknown

151

0.808

3446

19

4-Acetoxy-3,6-dimethoxy-8-

[2-(N-methylacetamido)]ethylphenanthrene

395

280

0.830

3515

20

N-Acetylnornarcotine

441

248

0.857

3601

21

(E)-N-Acetylanhydronornarceine

455

193

0.907

3757

22

(1R,9S)-1-Acetoxy-N-acetyl-1,9-

dihydro-anhydronornarceine

515

280

0.939

3848

23

(Z)-N-Acetylanhydronornarceine

455

193

0.950

3876

IS (C40)

n-Tetracontane (internal standard)

562

1.000

4000

Source: Reprinted from Forensic Science International, vol. 114, No. 2, L. Strömberg and others,

“Heroin impurity profiling: a harmonization study for retrospective comparisons”, pp. 67-88, Copyright

2000, with permission from Elsevier.

a

Based on n-tetracontane = 1.000.

---

70

Methods for impurity profiling of heroin and cocaine

Figure V.

Capillary gas chromatograms of a cocaine hydrochloride sample 

and a cocaine base sample

a

(A = cocaine hydrochloride sample; B = cocaine base sample)

Source: J. F. Casale and R. W. Waggoner, Jr., “A chromatographic impurity signature profile analysis

for cocaine using capillary gas chromatography”, Journal of Forensic Sciences, vol. 36, No. 5 (1991),

pp. 1312-1330. Copyright ASTM International. Reprinted with permission.

a

For peak identification, see table 4.

---

Annex III

71

Table 4:

Retention times for cocaine impurities in the capillary gas 

chromatograms in figure V

Peak

Compound

Retention time (min)

1

Benzoic acid

a

2.60

2

Anhydroecgonine methyl ester

3.52

3

Anhydroecgonine

a

4.10

4

trans-Cinnamic acid

a

4.36

5

Ecgonine methyl ester

a

4.94

6

Ecgonine

b

5.45

8

Tropacocaine

10.81

9

para-Fluorococaine

c

14.68

10

Cocaine

15.45

11

Benzoylecgonine

a

16.04

12

Norcocaine

d

16.26

13

beta-Truxinic acid

b

17.61

14

alpha-Truxillic acid

b

17.89

15

cis-Cinnamoylecgonine methyl ester

18.47

16

trans-Cinnamoylecgonine methyl ester

20.55

17

N-Formyl cocaine

22.93

a

Chromatographed as the O-TMS derivative.

b

Chromatographed as the di-O-TMS derivative.

c

Internal standard (ISTD).

d

Chromatographed as the N-TMS derivative.

Source:  J. F. Casale and R. W. Waggoner, Jr., “A chromatographic impurity signature profile analysis

for cocaine using capillary gas chromatography”, Journal of Forensic Sciences, vol. 36, No. 5 (1991),

pp. 1312-1330. Copyright ASTM International. Reprinted with permission.

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