The interference of putrefactive bases in the analysis of biological materials for drugs

A demonstration of the use of ultra-performance liquid chromatography–mass spectrometry [UPLC/MS] in the determination of amphetamine-type substances and ketamine for forensic and toxicological analysis

We have recently seen the emergence of ultra-performance liquid chromatography (UPLC) coupled to mass spectrometry as an alternative to traditional high-performance liquid chromatography techniques. The strengths of UPLC technology promote the ability to separate and identify drug compounds with significant gains in resolution and sensitivity and marked reductions in the overall time of analysis. As increased throughput is the desire of the practical toxicology laboratory, the aim of this study was to trial commercially available technology by assessment of the separation of several commonly encountered amphetamine-type substances. From injection of a poly-drug reference standard and whole blood extract, we successfully separated and identified amphetamine, methamphetamine, ephedrine, pseudoephedrine, phentermine, MDA, MDMA, MDEA and ketamine in less than 3 min using the Acquity UPLC-Micromass Quattro Micro API MS instrumentation (Waters Corporation, USA). In addition to this significant reduction in overall run time, all peaks exhibited acceptable resolution using selected ion recording (SIR), with analysis indicating the capability to separate 5-11 peaks in 1.75 min using the current system parameters. From this introductory data, it is therefore indicated that the technological advancements defining ultra-performance liquid chromatography will allow it to serve as a powerful analytical tool for rapid throughput analysis.

Product ion mass spectra of amphetamine-type substances, designer analogues, and ketamine using ultra-performance liquid chromatography/tandem mass spectrometry

This paper describes the application of ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) technology to separate and identify amphetamine-type substances (amphetamine, methamphetamine), common and novel designer analogues (MDA, MDMA, PMA, 4-MTA, MBDB), and ketamine using Acquity UPLC/Micromass Quattro Micro API mass spectrometer instrumentation (Waters Corporation, USA). From injection of drug reference standards, it was demonstrated that these compounds can be identified by product ion mass spectra in less than 4 min total analysis time, indicating that the technological advancements associated with UPLC/MS/MS allow it to serve as a powerful analytical tool for high-throughput testing. In addition to demonstrating the separation and response of these drug compounds under the stated UPLC/MS/MS conditions, we believe the acquired product ion spectra will be a beneficial reference to laboratories interested in incorporating the use of this technology in the routine analysis of drugs of abuse.

Effect of specimen storage and preservation on toxicological analyses of urine

1. The stability of nineteen classes of drugs or their metabolites in urine specimens, for the purpose of toxicological screening has been studied for periods of up to thirty-six weeks. 2. The effect of specimen preservation by refrigation and by the addition of boric acid, chloroform, sodium fluoride, mercuric chloride, and buffers, has been assessed. 3. With the exception of flurazepam, glutethimide, and secobarbital, specimens may be retained at room temperature for periods in excess of six weeks without deterioration. 4. Preservation by the addition of sodium fluoride (5 g/l) followed by freezing, thawing, and filtration significantly prevents specimen deterioration, and may be used as the method of choice.

Interfering basic materials in urine from racing greyhounds

Three quinoline amines, 2-aminomethylquinoline, 2-hydroxymethylquinoline and quinaldine (2-methylquinoline), are identified in greyhound urine. These amines can interfere in the analysis of greyhound material for basic drugs. This is a special problem in ultraviolet spectrometry since their extinction coefficients are high. Reference analytical data for these quinoline amines and for six related compounds are given. The techniques used are infrared spectrometry, ultraviolet spectrometry, fluorometry, thin-layer chromatography, gas chromatography and mass spectrometry.

The detection, identification and measurement of indole, tryptamine and 2-phenethylamine in putrefying human tissue

Indole, tryptamine and 2-phenethylamine are putrefactive products which may be found in decaying human tissue. They may be identified by the data given found in decaying human tissue. They may be identified by the data given for infrared and ultraviolet spectrometry, fluorometry, thin layer and gas chromatography and mass spectrometry. Quantitative studies may be made using the gas chromatography method described. The rate of formation is affected by temperature and preservatives and may be prevented if necessary by the use of sodium fluoride. No relationship between the production of these materials (and alcohol) and time since the post-mortem examination could be established. The post-mortem examinations took place within 24 hours of death.

Experimental investigations in post-mortem protein degradation

Samples of thoracic fluid were obtained at regular intervals from the putrefying bodies of dead dogs. For quantitative estimation of the proteins two-dimensional immunoelectrophoresis was employed and for the amino acids and amines two-dimensional thin-layer chromatography. The results lead to speculation that the initially lagging proteolytic changes are due to catalysis of autoenzymes, whereas bacteriological processes are responsible for a distinct acceleration from the 20th day after death. At this time the amino-acid concentrations showed a marked increase, which is followed by a maximum of bacterial growth, that ultimately leads to a sudden regression of amino acids. Simultaneously amines appear. The drying up of the thoracic cavity after 35 to 45 days marks the change from liquefaction to the terminal decay.