Methods for impurity profiling of heroin and cocaine

58

Methods for impurity profiling of heroin and cocaine

(b)

Heroin trace-level impurities

Typical source

Desthebaine

Thebaine + Ac

2

O

4,6-Diacetoxy-3-methoxy-5-

[2-(N-methyl-acetamido)]ethylphenanthrene

Thebaine + Ac

2

O

4,6-Diacetoxy-3-methoxy-8-

[2-(N-methyl-acetamido)]ethylphenanthrene

Thebaine + Ac

2

O 

4,6-Diacetoxy-3-methoxyphenanthrene

Thebaine + Ac

2

O

6-O-,N-Diacetylnorcodeine

Codeine + O

2

+ Ac

2

O

6-O-,N-Diacetylnormorphine

Morphine + O

2

+ Ac

2

O + hydrolysis

3,6-Dimethoxy-4,5-epoxyphenanthrene

Thebaine + Ac

2

O

Hydrocotarnine

Noscapine + O

2

Meconine

(E)-3-[2-(N-Methylacetamido)ethyl)-

4,5-methylendioxy-6-methoxyphenyl]acrilic acid

Nocapine + Ac

2

O

Alpha-Methylmorphimethine

Morphine + Ac

2

O

Papaveraldine

Papaverine + O

2

Thebaol

Thebaine + Ac

2

O + hydrolysis

Triacetylnormorphine

Morphine + O

2

+ Ac

2

O

a

Ac

2

O = acetic anhydride. 

b

O

2

= oxidation.

c

Major decomposition product.

Table 2.

Heroin: adulterants 

(non-opiate cutting agents with pharmacological effects)

Acetylsalicylic acid

Diphenhydramine

N-Phenyl-2-Naphthalene

Allobarbital

Gluthetimide

N-Phenyl-2-Naphthylamine

Aminophenazon

Griseofulvin

Procaine

Antipyrine

Lidocaine (lignocaine)

Quinine

Ascorbic acid

Methaqualone

Salicylamide

Barbital

Methylphenobarbitone

Salicylic acid

Benzocaine

Nicotinamide

Strychnine

Bisphenol-A

Paracetamol (acetaminophen) 

Theophylline

(+ acetyl-paracetamol)

Caffeine

Phenacetin

Thiamine

Chloroquine

Phenazon

Xylazine

Cocaine

Phenobarbitone (phenobarbital)

Diazepam

Phenolphthalein

Table 3.

Heroin: diluents (cutting agents to dilute the sample) 

and processing by-products

Calcium carbonate

a

Iditol hexa-acetate 

Sodium chloride

Calcium chloride

Lactose/saccharose

Starch (usually corn)

Citric acid

Mannitol/mannit/sorbit

Sucrose

Fructose

Phthalic acid

Sucrose octa-acetate

Glucose Potassium 

chloride

Tartaric 

acid

Glycine

Sodium carbonate

a

Calcium carbonate is almost always present as a processing by-product, almost never as a cutting agent (diluent).

Table 1.

Alkaloidal impurities in heroin and their sources (continued)

Opium; also a GC degradation product

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Annex II

59

B. 

Impurities in cocaine and their sources

Detailed information on the primary alkaloidal constituents of cocaine is available in the

United Nations manual Recommended Methods for Testing Cocaine: Manual for Use by

National Narcotics Laboratories (ST/NAR/7).

In the tables below, major components are > 1% by weight (w/w); minor components

are usually < 1% w/w; and trace components are usually < 0.1% w/w (typically requiring

an extraction step).

Table 4.

Alkaloidal impurities in cocaine and their sources

(a)

Major and minor components

Typical source

Anhydroecgonine

Gas chromatography (GC) artefact

Anhydroecgonine methyl ester

GC artefact

Benzoic acid

Hydrolysis of cocaine

Benzoylecgonine

Hydrolysis of cocaine, also found in coca

leaf but thought not to be extracted in the

clandestine process

Trans-cinnamic acid

Hydrolysis of cis- and  trans-cinnamoylcocaine

Cis-cinnamoylecgonine (often at trace level)

Hydrolysis of cis-cinnamoylcocaine

Trans-cinnamoylecgonine (often at trace level)

Hydrolysis of trans-cinnamoylcocaine

Cis-cinnamoylcocaine

Coca leaf

Trans-cinnamoylcocaine

Coca leaf

Ecgonine

Hydrolysis of cocaine, also found in coca

leaf, but thought not to be extracted in the

clandestine process

Ecgonine methyl ester

Found in coca leaf and occurs due to cocaine

hydrolysis; most probably is not extracted in

the clandestine process

N-formyl-cocaine

O

2

,

a

not present in coca leaf

Norcocaine

O

2

, not known to be present in coca leaf

Pseudoecgonine methyl ester

GC artefact: direct injection in MeOH of

cocaine base (crack) containing traces of

NaHCO

3

Truxillic acid(s)

Hydrolysis of truxillines

Truxillines

Coca leaf, the total content of all isomers

can be more than 10% of an unadulterated

cocaine sample. 11 theoretical diastereomers–

11 observed.

Truxinic acid(s)

Hydrolysis of truxillines

(b)

Cocaine trace-level impurities

Typical source

Acetoxyecgonine methyl ester

Coca leaf

N-Benzoylnorcocaine

Possibly a GC artefact 

6-exo-Benzoyloxytropine

Coca leaf

Benzoyltropine

Coca leaf

Butyroylecgonine methyl ester

Coca leaf

Cis-cinnamoyltropacocaine

Coca leaf

Trans-cinnamoyltropacocaine

Coca leaf

2’-Furanoylecgonine methyl ester

Coca leaf

3’-Furanoylecgonine methyl ester

Coca leaf

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