Segmental analysis of amphetamines in hair using a sensitive UHPLC-MS/MS method

Surface-enhanced Raman spectroscopy hair analysis after household contamination

Trace evidence found at crime scenes is rarely in an unsullied condition. Surface-enhanced Raman spectroscopy (SERS) is a modern analytical technique that can be used for the detection of artificial hair colourants (S. Higgins and D. Kurouski, Surface-Enhanced Raman Spectroscopy Enables Highly Accurate Identification of Different Brands, Types and Colors of Hair Dyes, Talanta, 2022, 251, 123762). However, contaminants pose a problem to collecting accurate spectra from the dyes. In this study, we sought to analyze how the different physical properties of contaminants can influence the collected spectra. We utilized 11 household substances of varying viscosity and opacity to contaminate hair dyed with permanent black or semi-permanent blue dyes. We discovered that contaminant opacity generally does not affect the spectral quality but that high contaminant viscosity does and that acidic substances could destroy the colourant's spectral identity altogether. Cleaning the contaminated hair with a water rinse allowed the underlying colourant to be identified in 21 out of 22 cases. Overall, this study provided a clearer understanding of the capabilities and limitations of SERS in forensic hair analysis.

Role of Race/Ethnicity, Sex, and Age in Surface-Enhanced Raman Spectroscopy- and Infrared Spectroscopy-Based Analysis of Artificial Colorants on Hair

Forensic microscopy has been used in forensic hair analysis to determine the racial origin of hair samples. However, this technique is subjective and often inconclusive. Although, to a large extent, this problem can be solved with the use of DNA analysis, which is capable of identifying the genetic code, biological sex, and racial origin from a strand of hair, this PCR-based analysis of hair is time- and labor-consuming. Infrared (IR) spectroscopy and surface-enhanced Raman spectroscopy (SERS) are emerging analytical techniques that can be used to advance forensic analysis of hair by enabling confirmatory identification of hair colorants. Having said that, it remains unclear whether the race/ethnicity, sex, and age of individuals should be considered upon IR spectroscopy- and SERS-based analysis of hair. Our results showed that both techniques enabled robust and reliable analyses of hair of different races/ethnicities, sexes, and age groups colored using four different permanent and semipermanent colorants. We also found that SERS could be used to identify the race/ethnicity, sex, and age of the individuals via spectroscopic analysis of colored hair, whereas IR spectroscopy was capable of accurately revealing this important anthropological information only from uncolored hair. These results outlined some advantages and limitations of both vibrational techniques in the forensic examination of hair samples.

Effects of crime scene contaminants on surface-enhanced Raman analysis of hair

Forensic analysis of hair is important as hair is one of the most commonly examined forms of trace evidence found at crime scenes. A growing body of evidence suggests that surface-enhanced Raman spectroscopy (SERS), a label-free and non-destructive analytical technique, can be used to detect and identify artificial colorants present on hair. However, hair collected at crime scenes is often contaminated by substances of biological and non-biological origin present at such locations. In this study, we investigate the extent to which four contaminants, saliva, blood, dirt, and bleach can alter the accuracy of SERS-based detection and identification of both permanent and semi-permanent colorants present on hair. Our findings show that saliva and dirt reduce the intensity of the colorants' signals but do not obscure their detection and identification. At the same time, an exposure of the colored hair to bleach or the presence of blood eliminates SERS-based analysis of artificial dyes present on such samples. We identified the procedure that can be used to remove blood contamination, which, in turn, enables identification of the hair colorants on such pre-cleaned samples. However, bleach treatment irreversibly eliminates SERS-based detection of artificial colorants on hair. These findings expand our understandings about the potential of SERS in forensic investigation of colorants on trace hair evidence.

A Retrospective of Prevalence of Drugs of Abuse by Hair Analysis in Shanghai using LC–MS-MS

This study presents a retrospective analysis of the prevalence of drug abuse in Shanghai by hair analysis. Files and toxicology analysis results of a total of 5,610 cases requesting for hair analysis of abused drugs at the Academy of Forensic Science (AFS) in Shanghai over 12 months between August 2018 and July 2019 were reviewed. All cases of drug abuse identified by hair analysis were from the public security organs in Shanghai, China. Hair samples were analyzed for drugs of abuse and related metabolites, mainly including amphetamine (AMP), methamphetamine (MA), 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyamphetamine (MDA), tetrahydrocannabinol (THC), ketamine (K), norketamine (NK), cocaine (COC), benzoylecgonine, morphine, 6-acetylmorphine, flunitrazepam, and 5-methoxy-N,N-diisopropyltryptamine (5-MeO-DIPT), using liquid chromatography–tandem mass spectrometry (LC–MS-MS). Among the 5,610 cases, 1,713 (30.5%) were positive for drugs of abuse, with amphetamine-type stimulants (ATS) (57%), including amphetamines (AMP and MA) (48%), MDMA and MDA (9%), being the most frequently detected drugs, followed by THC (14%), COC (8%), 5-MeO-DIPT (8%), and K (7%). The majority (75%) of positive hair samples were from male subjects. Overall, 77% of abusers were younger than 44 years old. The proportion of female subjects (22.3%) under 24 years was larger than that of male subjects (7.8%). There were 132 cases (7.7%) in which more than one type of drug was detected among 1,713 drug-positive cases. The most common combination was MDMA and K. The present study characterizes the current toxicological profile of drug abuse cases and provides a scientific basis for drug abuse prevention. Moreover, the hair concentration distributions of the commonly abused drugs in positive cases have been reported.

Surface-Enhanced Raman Analysis of Underlaying Colorants on Redyed Hair

Forensic examination of hair evidence can help with establishing a connection between a suspect and a crime scene or demonstrate the absence of such connections. Currently, it is primarily done by a subjective microscopic examination which can only elucidate the species of origin and, if human, the part of the body the hair came from. Several years ago, surface-enhanced Raman spectroscopy (SERS) was proposed for advanced forensic analysis of hair ( Kurouski , D. ; Van Duyne , R. P. In situ detection and identification of hair dyes using surface-enhanced Raman spectroscopy (SERS) . Anal. Chem. 2015 , 87 , 2901 - 2906 . DOI: 10.1021/ac504405u ). It was shown that SERS could be used to determine whether hair was dyed or not and even reveal what commercial hair colorant was used. Expanding upon those findings, we show that SERS is capable of probing the original colorant even if hair was redyed afterward. Specifically, we were able to detect and identify the underlaying blue semipermanent colorant on hair redyed by both black semipermanent and black permanent colorants. We also demonstrate that original black permanent colorant could be detected by SERS if the hair was recolored by blue semipermanent dye. However, it could not if the hair was recolored by another (blue or black) permanent dye. We also provide experimental evidence that SERS can be used to detect the dye on hair colored more than two months prior to its spectroscopic examination. These experimental findings substantially expand capabilities of SERS in forensics.

Comparison of Measures of Adherence to Human Immunodeficiency Virus Preexposure Prophylaxis Among Adolescent and Young Men Who Have Sex With Men in the United States

Background

Young men-who-have-sex-with-men (MSM) are disproportionately impacted by human immunodeficiency virus (HIV). Preexposure prophylaxis (PrEP) could reduce HIV acquisition among youth, but suboptimal adherence threatens effectiveness. Optimal metrics of PrEP adherence among adolescents have remain undefined.

Methods

The Adolescent Trials Network 110/113 studies provided daily oral PrEP with tenofovir (TFV) disoproxil fumarate/emtricitabine over 48 weeks to a diverse population of MSM (aged 15-22 years). Self-reported adherence was assessed and PrEP drug concentrations measured from hair and dried blood spot (DBS) samples; 23% of participants received Wisepill electronic monitoring devices. The average number of PrEP doses per week taken was estimated, and concordance between measures assessed.

Results

Among 243 participants, hair samples were collected at 1186/1238 (96%) person-visits. The concordance of TFV levels in hair and TFV-diphosphate in DBS around thresholds consistent with taking ≥4 and 7 PrEP doses/week was high (76% and 80%). Hair and DBS concentrations correlated poorly with self-report and Wisepill metrics. Through week 12, 40%-60% of participants (by hair and DBS), ≤31% (Wisepill), and >85% (self-report) were estimated to have taken ≥4 PrEP doses/week (a threshold associated with protection among MSM). For all measures except self-report, adherence declined over time, with half of participants taking <2 doses/week by week 48.

Conclusions

Among youth on PrEP, adherence waned over time. Self-report overestimated adherence, and use of Wisepill was limited. Hair collection was highly acceptable and provided similar interpretations to DBS. Incorporation of either metric in future PrEP studies among youth could identify suboptimal adherence and trigger interventions.

Maternal and neonatal hair and breast milk in the assessment of perinatal exposure to drugs of abuse

Perinatal exposure to one or more drugs of abuse can affect the neonate temporarily or permanently. In addition to meconium, the evaluation of perinatal exposure to drugs of abuse has been achieved by testing biological matrices coming from the newborn (neonatal hair) and from the pregnant or nursing mother (maternal hair and breast milk). These matrices have the advantage of noninvasive collection and account for a sizable time window of active and passive exposure. Sensitive and specific analytical methods are required to determine minute amounts of drugs of abuse and metabolites in these matrices. The present manuscript reviews the newest analytical methods developed to detect drugs of abuse as well as ethanol biomarkers in maternal and neonatal hair and breast milk.

In situ detection and identification of hair dyes using surface-enhanced Raman spectroscopy (SERS)

Hair is one of the most common types of physical evidence found at a crime scene. Forensic examination may suggest a connection between a suspect and a crime scene or victim, or it may demonstrate an absence of such associations. Therefore, forensic analysis of hair evidence is invaluable to criminal investigations. Current hair forensic examinations are primarily based on a subjective microscopic comparison of hair found at the crime scene with a sample of suspect's hair. Since this is often inconclusive, the development of alternative and more-accurate hair analysis techniques is critical. In this study, we utilized surface-enhanced Raman spectroscopy (SERS) to demonstrate that artificial dyes can be directly detected on hair. This spectroscopic technique is capable of a confirmatory identification of analytes with single molecule resolution, requires minimal sample, and has the advantage of fluorescence quenching. Our study reveals that SERS can (1) identify whether hair was artificially dyed or not, (2) determine if a permanent or semipermanent colorants were used, and (3) distinguish the commercial brands that are utilized to dye hair. Such analysis is rapid, minimally destructive, and can be performed directly at the crime scene. This study provides a novel perspective of forensic investigations of hair evidence.

Recent trends in analytical methods and separation techniques for drugs of abuse in hair

Hair analysis of drugs of abuse has been a subject of growing interest from a clinical, social and forensic perspective for years because of the broad time detection window after intake in comparison to urine and blood analysis. Over the last few years, hair analysis has gained increasing attention and recognition for the retrospective investigation of drug abuse in a wide variety of contexts, shown by the large number of applications developed. This review aims to provide an overview of the state of the art and the latest trends used in the literature from 2005 to the present in the analysis of drugs of abuse in hair, with a special focus on separation analytical techniques and their hyphenation with mass spectrometry detection. The most recently introduced sample preparation techniques are also addressed in this paper. The main strengths and weaknesses of all of these approaches are critically discussed by means of relevant applications.