Artemisia Dona

Zinc: a multipurpose trace element

Zinc (Zn) is one of the most important trace elements in the body and it is essential as a catalytic, structural and regulatory ion. It is involved in homeostasis, in immune responses, in oxidative stress, in apoptosis and in ageing. Zinc-binding proteins (metallothioneins, MTs), are protective in situations of stress and in situations of exposure to toxic metals, infections and low Zn nutrition. Metallothioneins play a key role in Zn-related cell homeostasis due to their high affinity for Zn, which is in turn relevant against oxidative stress and immune responses, including natural killer (NK) cell activity and ageing, since NK activity and Zn ion bioavailability decrease in ageing. Physiological supplementation of Zn in ageing and in age-related degenerative diseases corrects immune defects, reduces infection relapse and prevents ageing. Zinc is not stored in the body and excess intakes result in reduced absorption and increased excretion. Nevertheless, there are cases of acute and chronic Zn poisoning.

The cannabinoid content of marihuana samples seized in Greece and its forensic application

Abstract The three major cannabinoids, Δ 9 -tetrahydrocannabinol (Δ 9 -THC), cannabidiol (CBD) and cannabinol (CBN) were identified and determined quantitatively using a GCD (GC–EI) instrument, in samples of illicit herbal cannabis, seized by Customs and Police authorities in two areas of Greece (Ipiros and Lakonia) during 1996. These samples were sent by the above authorities to the Department of Forensic Medicine and Toxicology, University of Athens, for forensic chemical analysis. The cannabinoid content of these samples led to the classification of cannabis into two chemical phenotypes and to the differentiation of resinous and textile plants by using three different classification indexes. The cannabinoid content of cannabis plants is of forensic value in determining the geographical origin of cannabis samples, since it can be used for their classification, allocating this way the area of cultivation of the relative plants. The forensic aspects of cannabis classification are discussed.

Validated GC/MS method for the simultaneous determination of clozapine and norclozapine in human plasma. Application in psychiatric patients under clozapine treatment

A sensitive and specific GC/MS method for the determination of clozapine (CLZ) and its major metabolite norclozapine (NCLZ), in plasma has been developed, optimized and validated. Specimen preparation includes solid-phase extraction of both analytes using Bond-Elut Certify cartridge and further derivatization with TFAA. Clozapine-d8 was used as internal standard for the determination of CLZ and NCLZ. Limits of detection were 0.45 ng/mL for CLZ and 1.59 ng/mL for NCLZ, while limits of quantification were 1.37 ng/mL for CLZ and 4.8 ng/mL for NCLZ, as calculated by the calibration curves. The calibration curves were linear up to 600 ng/mL for CLZ and NCLZ. Absolute recovery ranged from 82.22% to 95.35% for both analytes. Intra- and interday accuracy was less than 7.13% and --12.52%, respectively, while intra- and interday precision was between 9.47% and 12.07%, respectively, for CLZ and NCLZ. The method covers all therapeutic range and proved suitable for the determination of CLZ and NCLZ not only in psychiatric patients but also in forensic cases with clozapine implication.

Biomarkers of opiate use

The interpretation of toxicological findings is critical for the thorough investigation of the use and abuse of psychoactive substances. A positive analytical result for a sample taken could usually result in criminal proceedings and a punitive outcome for the defendant whose sample was analysed. The detection of markers of illicit opiate misuse is important both in the management of substance misuse and in the postmortem identification of illicit opiate use. The aim of this study was to emphasise the role of opiate biomarkers available at the laboratory and in the clinical environment. Urine remains the biological tool of choice for qualitative detection of illicit drug use in a clinical setting, while quantitative accuracy remains strictly the domain of blood. Accurate interpretation of the screening tests within a clinical setting alongside other relevant information remains the key to the usefulness of any test. Moreover, the finding of a morphine/codeine concentration ratio in blood exceeding unity is a strong evidence that the person had used heroin, as opposed to having taken a prescription analgesic drug containing codeine.

Development and validation of a GC/MS method for the simultaneous determination of levetiracetam and lamotrigine in whole blood.

A sensitive and accurate gas chromatography-mass spectrometric method was developed and validated for the simultaneous determination of levetiracetam and lamotrigine in whole blood. A solid-phase extraction (SPE) procedure using HF Bond Elut C18 columns followed by derivatization using N-methyl-N-tert-butyldimethylsilyl-trifluoroacetamide (MTBSTFA) with 1% tert-butyldimethylsilyl chloride (TBDMSCl) was used. In this assay, levetiracetam-d6 was used as internal standard. Limits of detection and quantification were 0.15 and 0.50 μg/mL, respectively, for both analytes. The method was proved to be linear within the concentration range of 0.50-50.0 μg/mL (R(2) ≥ 0.992) for both analytes. Absolute recovery was found to be at least 90.0 and 97.2% for levetiracetam and lamotrigine, respectively. Intra-day and inter-day accuracy values for both analytes were ranged from -6.5 to 4.2 and -6.6 to 3.0%, respectively, whereas their respective precision values were less than 11.4 and 8.3%. The developed method was successfully used in our laboratory for quantification of levetiracetam and lamotrigine blood concentrations during the investigation of forensic cases where these antiepileptic drugs were involved. This method could also be used for therapeutic drug monitoring purposes.

Stability of Morphine, Codeine, and 6‐Acetylmorphine in Blood at Different Sampling and Storage Conditions

The stability of drugs in biological specimens is a major concern during the evaluation of the toxicological results. The stability of morphine, codeine, and 6‐acetyl‐morphine in blood was studied after different sampling conditions: (i) in glass, polypropylene or polystyrene tubes, (ii) with addition of dipotassium ethylene diamine tetraacetic acid (K2EDTA) or sodium oxalate (Na2C2O4), and (iii) with or without the addition of sodium fluoride (NaF). Spiked blood samples were stored at two different temperatures (4 and −20°C), analyzed after different storage times and after three freeze–thaw cycles. Opiate concentrations were decreased in all conditions, but the most unstable was 6‐acetyl‐morphine. The addition of NaF as preservative improved the stability of opiates at all conditions studied, whereas the type of anticoagulant did not affect the stability of opiates. It was concluded that blood samples should be stored at −20°C in glass tubes containing oxalate and NaF for maximum stability.

Detection of "uncommon" tranquillizers-sedatives during screening toxicological analysis.

The determination of some ‘‘uncommon’’ tranquillizers-sedatives during a toxicological analysis is often difficult particularly when the analysis of biological samples concern cases of mild intoxications such as one tablet intake, driving under the influence of drugs, or when no case history exists. Therefore, we investigated the possibility of identifying the intake of subtoxic doses of four anxiolytic and/or sedative drugs, namely, zolpidem, zopiclone, chlormethiazole and buspirone, during the screening procedures for drug detection in biological fluids followed in our laboratory [1]. Urine from 20 healthy volunteers, who took one tablet of each drug (5 samples for each drug) were analyzed in this study. Urine samples were collected approximately 3 hours after the intake of a single tablet or capsule of each drug. Nine urine samples from known cases of individuals that had taken subtoxic doses of these drugs were also analyzed. The urine sampling took place 2 to 4 hours after the ingestion of the drugs. No cross reactivity was observed during urine screening by fluoroscence polarization immunoassayTDx (Abbott), by enzyme immunoassay ETS Plus system (Syva), or by Triage (Merck) for opiates, benzodiazepines, cocaine, amphetamines and cannabinoids. A general cross-reactivity assessment was not performed because this was not in the purposes of our study.  10 ml of the urine samples were extracted through Chem-Elut extraction columns (Varian, Harbor City, CA), as described by Lillsunde and Korte [2]. After the extraction, the eluent was evaporated to dryness under a stream of N and was used for TLC and 2 GC–MS analysis after reconstitution in 25 ml of MeOH. TLC screening was performed according to Lillsunde and Korte [2]. All four drugs or their metabolites could not be detected in urine. The urine extracts were further analyzed by GC–MS according to a standardized method that we use in our laboratory [1].

Toxicological analysis of formalin-fixed or embalmed tissues: a review.

During the autopsy of forensic cases, when there is no suspicion of drug use or chemical exposure, biological fluids may not be obtained for toxicological analysis, while specimens of tissues may be collected and preserved in a formalin solution for histological examination. When specific questions arise after the burial, the only possible options are the exhumation of an embalmed body or the toxicological analysis of the formalin-fixed specimens. The drug concentrations in these specimens can be altered due to the extraction efficiency and/or the chemical activity of the formalin solutions used during chemical fixation or embalming process. The aim of this paper is to review the published studies about the determination of specific groups of drugs in formalin-fixed or embalmed specimens and their stability after chemical fixation or embalming process. The analytical aspects of this determination are also discussed. The stability of drugs in formalin environment and the possible reaction of the drugs with formaldehyde, which is a highly reactive chemical substance, should always be considered during post-mortem/post-embalming forensic analysis. The additional analysis of the formalin solution in which the tissue was preserved is considered necessary. The identification and the evaluation of the possible degradation products or chemical derivatives are extremely useful during the interpretation of the results.

Fentanyls continue to replace heroin in the drug arena: the cases of ocfentanil and carfentanil

PurposeOcfentanil and carfentanil are two potent synthetic opioids that are analogues of fentanyl and are actively involved in the recent fentanyl crisis. The aim of this review is to provide all the available information on these two fentanyl analogues.MethodsAll reviewed information was gathered through a detailed search of PubMed and the World Wide Web using relevant keywords.ResultsLike most of the members of the family of fentanyls, they are either sold as heroin to unsuspecting users or used extensively to lace heroin street samples. Despite the fact that ocfentanil was studied clinically in the early 1990s, it did not manage to find its place in clinical practice. On the other hand, carfentanil is mainly used today as an anesthetic agent in large animals. Ocfentanil and carfentanil are used and abused extensively, mainly in Europe and in the United States. As a result, they are the cause of some verified intoxication cases and deaths worldwide. This review provides information concerning chemistry, synthesis, prevalence, pharmacology, and toxicology, as well as the current legal status of these two fentanyl analogues. Analytical methods developed for the determination of ocfentanil and carfentanil in biological specimens and seized materials, as well as related intoxication and lethal cases are also presented.ConclusionsOcfentanil and carfentanil are undeniably very dangerous opioid drugs and a very serious matter of concern for public safety. The authorities should take the appropriate actions to avoid the expansion of this threat by taking proper and prompt measures.

Development and validation of a GC–MS method for the determination of hydroxyzine and its active metabolite, cetirizine, in whole blood

HighlightsA GC–MS method was developed and validated for the simultaneous determination of hydroxyzine and its active metabolite, cetirizine, in whole blood.The developed method provided significant advantages regarding sensitivity and linear dynamic range of related, previously published, methods.The method can be used during the investigation of clinical and forensic toxicology cases.The developed method was successfully applied during the investigation of clinical cases where these antihistamines were detected.The method could also be applied to pharmacokinetic studies concerning these antihistamines and the determination of more antihistamines in blood after proper optimization and validation. Abstract A simple, rapid, sensitive and accurate gas chromatography–mass spectrometric method was developed and validated for the simultaneous determination of hydroxyzine and cetirizine in whole blood. Solid‐phase extraction procedure using Bond Elut LRC Certify II columns was used for the isolation of hydroxyzine and cetirizine from 1 mL whole blood followed by derivatization with a mixture of acetic anhydride:n‐propanol (1:1, v/v). Limits of detection and quantification were 1.50 and 5.00 ng/mL, respectively. The assay was linear within the concentration range of 5.00–1000.0 ng/mL and the correlation coefficient was R2 ≥ 0.993 for both analytes. Absolute recovery was determined at three quality control concentration levels and was found to be at least 87.2% for both substances. Intra‐day and inter‐day accuracy values for both hydroxyzine and cetirizine were ranged from −1.2 to 3.8% and −2.7 to 2.0%, respectively, at the three concentration levels studied, whereas their respective intra‐day and inter‐day precision values were less than 9.9 and 6.5%, respectively, in terms of relative standard deviation (%RSD). The developed method was successfully applied for the quantification of hydroxyzine and cetirizine concentrations in whole blood, during the investigation of clinical cases where these two antihistamines were detected.