Analysis of illicit diamorphine preparations by high-pressure liquid chromatography

Validation of a straightforward high performance liquid chromatographic method for morphine quantitation

Background

Morphine is illegal to use unless it is prescribed by a medical doctor. This compound is commonly abused in the form of illicit heroin.

Methods

An easy-to-use method for determining morphine in illicit heroin using high performance liquid chromatography-photodiode array detector (HPLC-PDA) was developed. With the aid of 50:50 acetonitrile:ammonium formate, this target compound traveling in a pentafluorophenyl (PFP) column was successfully separated from other compounds frequently present in the heroin matrix.

Results

The method was precise with an intra-day relative standard deviation (RSD) ≤ 0.8% and inter-day RSD < 5%. It was able to detect as low as 0.001 mg/mL morphine. The detector’s response was linear (R² > 0.999) and reliable for morphine quantitation from 0.005 up to 1 mg/mL. Through recovery studies, accuracy of the method was averagely estimated to be 89.54–101.91%.

Conclusions

This method saves time in terms of mobile phase preparation and cuts cost by excluding additional purchase of expensive chemicals. More importantly, it proves to be able to determine the target analyte with sufficient accuracy and precision.

Heroin in the United Kingdom: different forms, different origins, and the relationship to different routes of administration

Heroin exists in the United Kingdom in several different forms, which vary not only in their country of origin and purity, but also in their suitability for use by either injecting or by 'chasing the dragon'. The availability of these different forms of heroin has varied considerably over time. A review of the characteristics and availability of these various forms of heroin in recent years is presented, accompanied by consideration of their probable intended use by injection or by 'chasing the dragon'. Samples of black market heroin in the salt form are usually used by injection, whereas the base form is usually taken by 'chasing the dragon'. The heroin yield to the drug user from samples of heroin taken by 'chasing the dragon' varies according to its base or salt format and according to the presence of other drugs in the sample. Heroin samples from different countries of production mostly conform to either base or salt form. Novel approaches at the macro level to prevention and control of heroin-related problems through influence upon this complex heroin market-place should now be considered.

Comparative analysis of heroin and cocaine seizures

In this brief review the analytical techniques mainly used for comparative analysis of both cocaine and heroin seizures are reported. The characterization of illicit samples is carried out by means of a variety of techniques including thin-layer chromatography, high-performance liquid chromatography, gas chromatography and capillary electrophoresis. By means of these technique it is possible to resolve some component in illicit drugs and their application for comparative analyses is described in this review. Owing to the complexity and the variability of the mixture related to the origin and manufacturing impurities a unique analytical approach based on the application of a single technique it is not sufficient to achieve the requested global characterization of the sample for comparative purposes. Generally a complete characterization is obtained focusing on the identification of minor and major components, origin and manufacturing impurities other than trace compounds such as solvent residues. Nevertheless the application of a single robust methods able to resolve any possible significant marker compounds, is still not described and there is a need for a standardized general procedure suitable for a complete cross-examination of analytical data related to comparative analyses that can be carried out at an international level.

High-performance liquid chromatographic determination of morphine in biological samples: an overview of separation methods and detection techniques

High-performance liquid chromatogrpahy with electrochemical detection at present suits most of the needs of toxicologists for the determination of morphine and some related compounds in biological samples, although fluorescence detection is still a useful alternative. Chemiluminescence detection may be promising, but needs further optimization of its coupling with HPLC to give the best performances. Morphine detection by absorbance spectrophotometry does not seem to allow the degree of sensitivity and selectivity from matrix interferences that is required in most instances. However, this approach is useful when morphine congeners undetectable by alternative means (i.e., heroin and morphine-3-glucuronide) are to be determined or when a general toxicological screening is required.

Comprehensive gas chromatographic analysis of heroin street samples

A comprehensive analytical approach for heroin street samples is faced with problems associated with differences in polarity, stability and physico-chemical properties of the various substances present. Difficulties with carbohydrates are of particular concern. In this method, which is suitable for screening purposes, 10 mg of sample is dissolved in acetonitrile-trifluoroacetic acid in the presence of methyl orange. Derivatization is then accomplished by O-silylation (MSTFA) and N-trifluoroacetylation (MBTFA). Compounds were detected by flame ionization after a capillary gas chromatographic separation and produced well shaped peaks for the majority of substances. Sugars gave multiple but reproducible chromatographic peaks. By direct derivatization of another aliquot of the solid sample a single predominant chromatographic peak can be obtained for sugars using MSTFA with MBTFA. Alternatively the more potent reagent MSHFB gives highly reproducible results.

Analytical studies on illicit heroin. III. Auto-interference in the colorimetric determination of strychnine in illicit heroin samples

The colorimetric determination of strychnine in illicit heroin samples, based on the reduction of strychnine followed by colour development with nitrite was checked. Interference by heroin was observed, as well as a strong interference by caffeine. It was concluded that results, based on this method, are not reliable.

Use of high-performance liquid chromatography to quantitate the opiate and sugar content of illicit heroin preparations

Two high-performance liquid chromatographic systems can be used to obtain the opiate and sugar content of illicit heroin preparations. The combined quantitative results can then be used to determine if the samples originate from a common source.

Capillary gas chromatographic analysis of illicit diamorphine preparations

An improved capillary gas chromatographic method for the analysis of illicit diamorphine preparation is reported. The method was able to resolve the impurities and more frequent adulterants and contaminants present in street heroin preparations with a diamorphine detection limit of 0.2 ng in split-less mode.

Determination of heroin and its metabolites by high-performance liquid chromatography

A method is described for the simultaneous determination of heroin (3,6-diacetylmorphine, DAM) and its two active metabolites 6-acetylmorphine and morphine in blood by high-performance liquid chromatography using a normal-phase column and a UV detector at 218 nm. The compounds are stabilized in blood by rapid freezing and recovered by a multistep liquid--liquid extraction. The mobile phase is acetonitrile--methanol (75:25, v/v) buffered to apparent pH 7 with ammonium hydroxide and acetic acid. Using l-alpha-acetylmethadol as an internal standard, UV detection and a 1-ml biofluid sample, the lower limit of sensitivity is 12.5 ng/ml. Commonly used narcotic analgesics including codeine, propoxyphene, meperidine, methadone and levorphanol do not interfere with the analysis. The method has been applied to blood samples from humans and rats. Extracts of blood from a patient who had received an intravenous dose of 14 mg of DAM contained DAM and both of its active metabolites.

Simple high-performance liquid chromatographic method for the separation of 3,6-diacetylmorphine hydrochloride (heroin) and hydrolysis products

The application of reversed-phase high-performance liquid chromatography to the measurement of 3,6-diacetylmorphine (DAM) hydrochloride and its degradation products is described. This method has been applied to study the kinetics of the DAM hydrolysis at 26 +/- 0.1 degrees and 48 +/- 0.1 degrees. The hydrolysis of DAM involved a two-step first-order sequential mechanism between pH 3 and 8.6. The first-order rate constants of each step at all pH levels have been determined. The pH rate profile was constructed from kinetic measurements and demonstrated that stability of DAM hydrochloride solutions was optimal at pH 4.3. This information is being applied to the development of parenteral dosage forms of DAM hydrochloride.

Quantitative determination of thebaine in Papaver bracteatum by high-pressure liquid chromatography

A method is described for the quantitative analysis of thebaine from Papaver bracteatum, using a single high-pressure liquid chromatographic column. The procedure gives base-line separation of thebaine without the need for gradient elution equipment, and can be completed within 12 min. Thebaine isolated by this technique was shown to be pure, regardless of the age of plant or plant part from which it was obtained.

Forensic aspects of high-pressure liquid chromatography

This paper reviews the applications of high-pressure liquid chromatography (HPLC) to forensic problems, and discusses some of the developments that have taken place in the use of the technique in the Metropolitan Police Laboratory. Preparation of octadecyltrichlorosilane-modified silica is described and some of the chromatographic characteristics of this material are investigated. Applications of HPLC to the analysis of cannabis, opium alkaloids, amphetamine-related materials, LSD and polynuclear hydrocarbons are described.

High-pressure liquid chromatography of drugs. II. An evaluation of a microparticulate cation-exchange column

A microparticulate cation-exchange column has been evaluated for the chromatography of thirty compounds selected as representative of a wide variety of drug substances. Although the column exhibited a strong partition effect besides the expected ion-exchange mechanism, the retention of drugs could be predictably influenced by variation of the eluent ionic strength and organic solvent content. For acidic drugs the column showed little selectivity (although a salting-out effect increased retention at high eluent ionic strengths), but for basic substances Partisil SCX may afford a useful separative medium offering reasonable chromatographic efficiency (HETP is approximately 0.1 mm). The column longevity, however, is at present questionable.

High-pressure liquid chromatography of drugs. An evaluation of an octadecylsilane stationary phase

The performance of a commonly used high-pressure liquid chromatographic stationary phase, octadecylsilane, has been evaluated for 30 compounds selected as representative of a wide variety of drug substances. Chromatographic behavior is found to be highly predictable on the basis of pKa and partition coefficient, and the stationary phase should be especially valuable for the separation of acidic and neutral drugs. For basic drugs, however, the column efficiency is poor, detracting from the overall usefulness.