Determination of Antidepressants in Hair via UHPLC-MS/MS as a Complementary Informative Tool for Clinical and Forensic Toxicological Assessments

Morphological and chemical profiling for forensic hair examination: A review of quantitative methods

Within the past two decades, there have been many studies for quantitative analysis on human hair samples. Microscopical and chemical analysis techniques have been used to analyze various aspects of hair regarding biological, chemical, anthropological, cosmetic, and forensic applications. Studies have attempted to develop quantification methods to increase the evidentiary value of hair in forensic casework. The literature reviewed in this paper provides some of the current techniques used for forensic examinations and quantitative methods. Although microscopical analysis has been scrutinized in the past, using chemical and microscopical techniques can provide a myriad of information. The extraction of DNA from hair provides high-value evidence; however, it may not be readily available and may yield inconclusive results. Hair analysis can be used for many forensic applications such as comparison, toxicology, and exposure analysis. In this article, we will review published research material regarding chemical and microscopical techniques for human hair analysis. Aspects considered for this review were the sample size requirement for analysis and the destructive nature of the instrumental method. This review will focus on both macro and micro quantitative methods for human hair analysis.

Concentrations of citalopram and escitalopram in postmortem hair segments

Hair analysis can provide information regarding previous drug intake and use patterns, as the drugs consumed are incorporated into the hair. Therefore, reference values for drugs in hair are valuable in forensic investigations, especially when evaluating drug intake and assessing drug tolerance. The aim of the study was to determine concentrations of citalopram, escitalopram, and their primary metabolites in hair segments from deceased individuals with mental illness. Concentrations in up to six months prior to death were evaluated and compared with the estimated daily doses. Hair samples collected from 47 deceased individuals, were segmented in one to six 1 cm segments, and extracted overnight in medium. The concentrations in hair were quantified via ultra-high-performance liquid chromatography-tandem mass spectrometry. Following this quantification, the extracts were reanalyzed qualitatively using a chiral method to distinguish between citalopram and escitalopram intake. We found hair concentrations (10-90 percentile (perc.)) of citalopram from 0.12 to 67 ng/mg with a median of 8.2 ng/mg (N = 40 individuals, n = 182 segments) and of escitalopram from 0.027 to 7.0 ng/mg with a median of 3.9 ng/mg (N = 4, n = 23). The metabolite-to-drug ratios in hair (10-90 perc.) of citalopram were 0.091-0.57 with a median of 0.30 (N = 39) and of escitalopram were 0.053-0.63 with a median of 0.41 (N = 3). No correlations were found between concentrations in the hair and the estimated daily dose. However, our results indicate higher concentrations in dark hair compared to light hair, given the estimated doses, and thus an influence of hair color on the results. A significant positive correlation was found between the concentration of citalopram in the proximal segment and the blood concentrations. The median R/S-ratio of citalopram in hair was 1.5 and was similar to previously reported ratios in blood. In the present study, we report concentrations of citalopram and escitalopram in postmortem hair and their relation to an estimated daily dose and thus contribute valuable information in forensic investigations.

Evaluation of decontamination procedures for drug testing in undamaged vs damaged hair

INTRODUCTION

Although substances incorporated by ingestion are strongly bound to hair, their loss may occur if aggressive decontamination procedures are applied, especially in highly damaged/porous hair.

AIMS

Evaluation of cleaning procedures using hair samples with different porosity obtained from ethanol or drug users (cocaine, heroin, methamphetamine, methadone, fentanyl, tramadol, diazepam, buprenorphine, dihydrocodeine, citalopram and trazodone). The effect of washing time and multiple wash steps with water and methanol were evaluated.

METHODS

Hair samples (n=16) were selected and evaluated according to: a) the drug pattern consumption, b) available amount, and c) hair porosity (c1 'cosmetic treatment', c2: storage time). Six of them were soaked with an aqueous deuterated analogue solution. The samples were cut in 1 cm segments and homogenized. All hair samples were then decontaminated one or six times with 1.5 mL of water or methanol during 1, 5, 15, 30, 60 and/or 90 min (n=1 to 3/sample, depending on the available amount of hair). Hair extracts were then cleaned up via an SPE or LLE extraction, while the washes were evaporated to dryness. All were thereafter reconstituted and analysed with routine UPLC-MS/MS methods.

RESULTS AND DISCUSSION

Although concentrations of parent drugs and/or metabolites presented a negative trend along the washing time with methanol (up to 80%), the compounds were relatively well retained in hair even after a 90 min wash in most samples. Their retention would depend mostly on the hair nature rather than their physicochemical properties (whether incorporated by ingestion and/or from external contamination). Moreover, parent drugs and/or metabolites were detected in the washes in most samples, and the ratio between hair and washes decreased along the washing time. More than 50% of the deuterated analogues soaked into hair were still present after the different washing steps.

CONCLUSION

Generally, the substances analysed were well retained in hair samples after different washing steps with water or methanol. Losses were observed more frequently for long term stored hair samples, after decontamination with methanol for more than 30 min. Therefore, prolonged or repeated cleaning with methanol should be avoided in general procedures.

Prevalence of cathinones and other new psychoactive substances in hair of parents and children of families with known or suspected parental abuse of conventional illegal drugs

BACKGROUND

Hair analysis of parents and their children was regularly used since 2011 as a diagnostic tool in a social support project for families with known or suspected abuse of conventional illegal drugs and revealed a high incidence of cocaine, cannabinoids, amphetamines, ecstasy and heroin. In this context, the prevalence of new psychoactive substances (NPS) in these families should be important for a realistic estimate of the situation.

METHODS

The extracts of 1537 hair samples from 318 children (age 1-14 years), 44 adolescents and 611 adults, which were collected and tested for conventional drugs between June 2016 and April 2021 and frozen at -20 °C, were reanalyzed by a validated LC-MS/MS method (limits of quantitation 5-24 pg/mg) for 33 cathinones, 10 phenylethylamines, 5 piperazines including the antidepressant trazodone, 2 tryptamines, 9 designer benzodiazepines, 4 synthetic opioids and 4 ketamine-like substances including phencyclidine.

RESULTS

Between one and up to five from 42 of these substances were detected in 227 samples (14.8%). The most frequently detected substances were benzedrone (62x), α-pyrrolidinovalerophenone (41x), N-ethylamphetamine (29x), dimethyltryptamine (13x) and pyrovalerone (11x). The quantification was possible only for 34 results of 15 drugs and the remaining majority of the results were unambiguously identified below LLOQ. The relative frequency of conventional drugs in the 227 NPS positive samples was higher than in all 1310 NPS negative samples for cocaine (69.6% vs. 56.0%), heroin (6-acetylmorphine 8.8% vs. 4.9%), amphetamine (16.3% vs. 7.7%) and MDMA (16.3% vs. 7.0%) but was similar for THC (38.3% vs. 36.3%) and benzodiazepines (1.8% vs. 1.7%). The high prevalence of N-ethylamphetamine can be explained as a byproduct of the illicit amphetamine synthesis from benzaldehyde and nitroethane rather than as a separate drug or as a combined metabolite of amphetamine and ethanol. The isolated appearance of 3-trifluoromethylphenylpiperazine in 9 hair samples collected in January 2017 can be caused either by its use as an NPS or by its formation as a metabolite of the medical drug flibanserin. The results were compared within 17 families whose members were tested at the same time and showed positive NPS results. The detected drugs agreed between both parents only in about half of the cases whereas the drugs found in children's hair was always detected also in hair of one or both parents.

CONCLUSION

The re-testing of hair extracts for NPS after long-time storage in frozen state enables an impression about the relative high prevalence in the tested population group, despite the limitation by partial degradation of the substances and the corresponding impossibility in quantitative assessments. In addition to conventional drugs, the hair test for these substances should be useful in unclear cases of child's welfare endangerment and in family law.

Current status of hair analysis in forensic toxicology in China

Hair analysis has been mainly used to document drug use history in abusers, drug-facilitated crime cases, doping control analysis and postmortem toxicology in the fields of forensic toxicology, clinical toxicology, and doping control. Hair analysis has also gained more attention in the last 30 years in China. Relevant technology has been promoted as more research has appeared concerning hair analysis, and consensus has been sought among forensic toxicologists regarding aspects such as hair decontamination treatment, detection of abused substances in hair, segmental hair analysis and interpretation of analytical results. However, there are still some limitations in the estimation of drug intake time and frequency by segmental hair analysis due to the different growth cycles evident within a bundle of hairs, the drug incorporation mechanism and sampling errors. Microsampling and imaging mass spectrometry (IMS) technology based on a single hair may be a good choice to estimate drug intake time more accurately. Analysis of hair root samples may also be used to document acute poisoning in postmortem toxicology, and the analysis of the hair shaft can document long-term use of drugs depending on the length of the hair being evaluated.

A Systematic Review of Metabolite-to-Drug Ratios of Pharmaceuticals in Hair for Forensic Investigations

After ingestion, consumed drugs and their metabolites are incorporated into hair, which has a long detection window, ranging up to months. Therefore, in addition to conventional blood and urine analyses, hair analysis can provide useful information on long-term drug exposure. Meta-bolite-to-drug (MD) ratios are helpful in interpreting hair results, as they provide useful information on drug metabolism and can be used to distinguish drug use from external contamination, which is otherwise a limitation in hair analysis. Despite this, the MD ratios of a wide range of pharmaceuticals have scarcely been explored. This review aims to provide an overview of MD ratios in hair in a range of pharmaceuticals of interest to forensic toxicology, such as antipsychotic drugs, antidepressant drugs, benzodiazepines, common opiates/opioids, etc. The factors influencing the ratio were evaluated. MD ratios of 41 pharmaceuticals were reported from almost 100 studies. MD ratios below 1 were frequently reported, indicating higher concentrations of the parent pharmaceutical than of its metabolite in hair, but wide-ranging MD ratios of the majority of pharmaceuticals were found. Intra- and interindividual differences and compound properties were variables possibly contributing to this. This overview presents guidance for future comparison and evaluation of MD ratios of pharmaceuticals.

Prevalence and concentrations of new designer stimulants, synthetic opioids, benzodiazepines, and hallucinogens in postmortem hair samples: A 13-year retrospective study

Hair samples are frequently analyzed in order to characterize consumption patterns of drugs. However, the interpretation of new psychoactive substance (NPS) findings in hair remains difficult because of lacking data for comparison. In this study, selected postmortem hair samples (n = 1203) from 2008 to 2020 were reanalyzed for synthetic cathinones, piperazines, phenethylamines, hallucinogens, benzodiazepines and opioids to evaluate prevalence data and concentration ranges. Hair samples were extracted using a two-step extraction procedure and analyzed using a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Overall NPSs were detected in 381 cases (31.6%). Many cases were tested positive for more than one NPS in the same time span. A variety of NPS with a large range of concentrations was observed. For better comparability and interpretation of positive cases in routine work, quantitation data for 13 NPS were calculated as percentiles. The most frequently detected NPS in this study were N-ethylamphetamine, α-pyrrolidinovalerophenone, mephedrone, benzedrone, metamfepramone, and 4-fluoroamphetamine. In conclusion, a high prevalence of these drugs was observed from postmortem hair samples. The results show a growing use of many different NPSs by mainly young drug-using adults. Consequently, NPS screening procedures should be included in forensic toxicology. Our quantitative data may support other toxicologists in their assessment of NPS hair concentrations.

Concentrations of Antidepressants, Antipsychotics, and Benzodiazepines in Hair Samples from Postmortem Cases

Certain postmortem case constellations require intensive investigation of the pattern of drug use over a long period before death. Hair analysis of illicit drugs has been investigated intensively over past decades, but there is a lack of comprehensive data on hair concentrations for antidepressants, antipsychotics, and benzodiazepines. This study aimed to obtain data for these substances. A LC-MS/MS method was developed and validated for detection of 52 antidepressants, antipsychotics, benzodiazepines, and metabolites in hair. Hair samples from 442 postmortem cases at the Institute of Legal Medicine of the Charité-University Medicine Berlin were analyzed. Postmortem hair concentrations of 49 analytes were obtained in 420 of the cases. Hair sample segmentation was possible in 258 cases, and the segments were compared to see if the concentrations decreased or increased. Descriptive statistical data are presented for the segmented and non-segmented cases combined (n = 420) and only the segmented cases (n = 258). An overview of published data for the target substances in hair is given. Metabolite/parent drug ratios were investigated for 10 metabolite/parent drug pairs. Cases were identified that had positive findings in hair, blood, urine, and organ tissue. The comprehensive data on postmortem hair concentrations for antidepressants, antipsychotics, and benzodiazepines may help other investigators in their casework. Postmortem hair analysis results provide valuable information on the drug intake history before death. Pattern changes can indicate if drug intake stopped or increased before death. Results should be interpreted carefully and preferably include segmental analysis and metabolite/parent drug ratios to exclude possible contamination.

[Development of High-resolution Methods for the Analysis of Drug Distribution in Biological Tissue Samples and Their Applications]

The abuse of drugs has become a serious social problem worldwide. Amphetamine-type stimulants such as methamphetamine are recreationally abused and can cause toxic effects in the body. Unfortunately, death from drug poisoning can occur due to careless intake. In postmortem examinations, the distribution of drugs in an entire organ gives valuable information for evaluating their toxicity. We developed methods to measure the distribution of drugs in organs using LC/MS and matrix-assisted laser desorption/ionization-imaging mass spectrometry (MALDI-IMS). The complementary use of the two methods provides more detailed information on the distribution and concentration of drugs in organs because the accurate quantification in LC/MS and small spatial resolution in MALDI-IMS are combined. On the other hand, it is important to elucidate the drug intake history of suspects and victims in drug-facilitated crimes (DFCs). Hair and nail samples are often used to confirm chronic drug intake because ingested drugs can stably remain in these specimens over several months. However, it is impossible to determine the day of drug ingestion in conventional segmental analysis of bulk samples. Therefore, we developed methods to cut hair strands at 0.4-mm intervals and nails at 0.2-mm intervals, which correspond to their respective growth rates over 1-2 d, to analyze the drugs in each segment efficiently using LC/MS. The microsegmental hair analysis method is applied to estimate the day of drug ingestion in DFC investigations. These methods could be applied to measure the distribution of compounds in various solid samples.

Accurate Estimation of Drug Intake Day by Microsegmental Analysis of a Strand of Hair by Use of Internal Temporal Markers

Background

Segmental hair analysis can be useful for estimating the time of drug intake. However, this estimation is currently only accurate to within several months. We previously conducted microsegmental analysis of a strand of hair to visualize drug distribution at a spatial resolution of 0.4 mm, which corresponds to daily hair-growth length. Herein, we describe a procedure for accurately estimating the day of drug intake by using internal temporal markers (ITMs) to mark a timescale in the analyzed strand of hair.

Methods

Five drugs were administered in a single dose to the subjects, and then administration was stopped for several weeks. Two subsequent cycles of drug administration and similar withdrawal were performed. For analysis, a strand of hair was plucked from the subject's scalp. The first intake day was considered as the unknown and the drugs administered second and third were regarded as the ITMs. The first intake day was estimated based on the distance from hair root end to 3 drug peaks and 3 known days (hair sampling and 2 ITM cycles).

Results

The drug concentration–hair segment curve had 3 peaks, which reflected the 3 drug cycles. The use of ITMs reduced the error of the true intake day to within 2 days, because the growth rate of the analyzed strand of hair was accounted for by the 2 ITMs.

Conclusions

The estimated accuracy showed little dependency on drug and individual variation. This procedure for estimating the time of drug intake down to a particular day can be used in drug-related crimes, drug abuse and compliance, and for medical diagnosis.

Micro-segmental hair analysis for proving drug-facilitated crimes: Evidence that a victim ingested a sleeping aid, diphenhydramine, on a specific day

Sleeping aids are often abused in the commission of drug-facilitated crimes. Generally, there is little evidence that a victim ingested a spiked drink unknowingly because the unconscious victim cannot report the situation to the police immediately after the crime occurred. Although conventional segmental hair analysis can estimate the number of months since a targeted drug was ingested, this analysis cannot determine the specific day of ingestion. We recently developed a method of micro-segmental hair analysis using internal temporal markers (ITMs) to estimate the day of drug ingestion. This method was based on volunteer ingestion of ITMs to determine a timescale within individual hair strands, by segmenting a single hair strand at 0.4-mm intervals, corresponding to daily hair growth. This study assessed the ability of this method to estimate the day of ingestion of an over-the-counter sleeping aid, diphenhydramine, which can be easily abused. To model ingestion of a diphenhydramine-spiked drink unknowingly, each subject ingested a dose of diphenhydramine, followed by ingestion of two doses of the ITM, chlorpheniramine, 14days apart. Several hair strands were collected from each subject's scalp several weeks after the second ITM ingestion. Diphenhydramine and ITM were detected at specific regions within individual hair strands. The day of diphenhydramine ingestion was estimated from the distances between the regions and the days of ITM ingestion. The error between estimated and actual ingestion day ranged from -0.1 to 1.9days regardless of subjects and hair collection times. The total time required for micro-segmental analysis of 96 hair segments (hair length: 3.84cm) was approximately 2days and the cost was almost the same as in general drug analysis. This procedure may be applicable to the investigation of crimes facilitated by various drugs.