Drug Testing and Analysis最新文献

{"title":"Comparative Evaluation of Smart Sampling for hCG Determination: A New Potential Direction in Protein Biomarker Analysis From Dried Microsamples","authors":"Ago Mrsa,&nbsp;Marijana Matijevic,&nbsp;Yvette Dehnes,&nbsp;Trine Grønhaug Halvorsen,&nbsp;Léon Reubsaet","doi":"10.1002/dta.3948","DOIUrl":"10.1002/dta.3948","url":null,"abstract":"<div>\u0000 \u0000 <p>Since the early 20th century, sampling biological matrices like blood on paper (dried blood spots [DBS]) has been vital in clinical analysis. While DBS microsampling is convenient for small molecules, extensive sample preparation can make LC-MS protein analysis impractical because of the time-consuming steps, especially for low-abundance proteins. Smart sampling, introduced in 2018, simplifies this by integrating sample preparation directly on the sampler. The work presented in this paper aims to compare a newly validated smart sampling method with two other methods: an in-house method based on immunocapture on magnetic beads and a commercial method that uses electrochemiluminescence immunoassay (ECLIA). The performance of the three hCG methods was compared using 21 single-blind serum samples. Linear regression analysis revealed strong correlations (all <i>R</i>² &gt; 0.91) between the actual sample concentrations and the results obtained from all three methods. Immunocapture with magnetic beads showed the strongest linear correlation (<i>R</i>² = 0.974). To assess agreement between the methods, Bland–Altman analysis was conducted. The comparison between smart sampling and magnetic beads showed an average bias of −5.2, with no significant trend in variation across the sample concentration range of 0.5–75 ng/mL. The smart sampling and ECLIA comparison revealed a bias of 0.4 ± 4 ng/mL, indicating even better agreement and consistent results. This paper presents the first-ever comparison of a smart sampling method with existing methods. The results highlight smart sampling as a promising new approach for bioanalysis and boost the technique as a viable alternative in protein biomarker analysis from complex matrices using LC-MS.</p>\u0000 </div>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"17 12","pages":"2390-2398"},"PeriodicalIF":2.7,"publicationDate":"2025-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145063058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"From Kratom to Semi-Synthetic Opioids: The Rise and Risks of MGM-15","authors":"Abhishek Gour,&nbsp;Sushobhan Mukhopadhyay,&nbsp;Allison Henderson,&nbsp;Ahmed Awad,&nbsp;Maria A. Seabra,&nbsp;Mallory Pullman,&nbsp;Francisco León,&nbsp;Stephen J. Cutler,&nbsp;Christopher R. McCurdy,&nbsp;Abhisheak Sharma","doi":"10.1002/dta.3952","DOIUrl":"10.1002/dta.3952","url":null,"abstract":"<div>\u0000 \u0000 <p>Kratom (<i>Mitragyna speciosa</i>), a plant native to Southeast Asia, has long been used for its stimulant and analgesic properties. 7-Hydroxymitragynine (7-HMG) is a potent and selective opioid agonist in vitro and demonstrates a potent opioid effect in living subjects, reversible by naloxone. It has been semi-synthesized into products that are readily available in retail and virtual shops. It is known that 7-HMG has earned the nickname “legal morphine,” and has gained popularity among users seeking pain relief and/or a “high” comparable with prescription opioids. Medicinal chemistry efforts have led to synthetic 7-HMG derivatives such as MGM-15, where stereospecific saturation of the imine N(1)–C(2) double bond increases opioid receptor affinity and activity. Despite its higher in vitro opioid potency, MGM-15 is currently sold in the US for human consumption as a “research chemical” in tablet form, even though there is an absence of this being studied in humans and obviously no FDA approval. In this study, we analyzed commercially available MGM-labeled tablets using UPLC–MS/MS and subsequently evaluated the binding affinities of purified MGM-15 across multiple opioid receptors. Tablets contained an average of 10.9 ± 0.2 mg (10.7 to 11.2 mg) of MGM-15, with no naturally occurring kratom alkaloids or illicit substances detected. MGM-15 shows greater hMOR and hDOR binding affinities than 7-HMG, indicating the potential for higher opioid effects and risks, emphasizing the urgent need for more research to advise regulation and hopefully prevent misuse and harm.</p>\u0000 </div>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"17 12","pages":"2384-2389"},"PeriodicalIF":2.7,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145038709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detection of Anabolic Androgenic Steroids and Steroid Esters—Comparing Dried Blood Spots Collection Devices and Urine Samples","authors":"Tina Suominen,&nbsp;Jeanette von Walden,&nbsp;Laura Harju,&nbsp;Anton Pohanka,&nbsp;Jenny Schulze,&nbsp;Mikael Lehtihet,&nbsp;Lena Ekström","doi":"10.1002/dta.3950","DOIUrl":"10.1002/dta.3950","url":null,"abstract":"<p>Dried blood spots (DBS) have emerged as a promising complement, and in some settings, an alternative, to urine for anabolic androgenic steroid (AAS) testing, offering advantages such as minimal invasiveness, simplified storage, and transportation. This study evaluated two DBS collection devices—cellulose-based Capitainer-B50 and polymer-based Tasso-M20—and compared results with traditional urine analysis. Ten self-reported AAS users were recruited and provided matched urine and DBS samples. High agreement between the two DBS devices was observed, although Capitainer-B50 showed a slightly greater detection rate, likely due to a higher sample volume (50 μL vs. 17.5 μL) improved analyte recovery, and lower background noise. Notably, DBS enabled detection of testosterone use in all 10 participants, while urine testing missed two cases with naturally low urinary testosterone/epitestosterone (T/E) ratios (most likely UGT2B17 del/del carriers). Moreover, the differentiation between prescribed and illicit use of testosterone esters was also possible in DBS, but not in urine testing, while nandrolone detection in DBS was limited at low concentrations. The findings support DBS as a sensitive and practical tool for AAS detection and provide critical advantages in detecting doping with testosterone esters in individuals with prescribed testosterone therapy and in UGT2B17 deletion carriers.</p>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"17 12","pages":"2374-2383"},"PeriodicalIF":2.7,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://analyticalsciencejournals.onlinelibrary.wiley.com/doi/epdf/10.1002/dta.3950","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145028625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impurity Profiling of ATS Synthesized From Ring-Substituted APAAN and MAPA Analogs","authors":"Deanna Langone,&nbsp;Ben Painter,&nbsp;Clark Nash,&nbsp;Janneke W. Hulshof,&nbsp;Sander Oldenhof,&nbsp;Martin R. Johnston,&nbsp;K. Paul Kirkbride","doi":"10.1002/dta.3946","DOIUrl":"10.1002/dta.3946","url":null,"abstract":"<div>\u0000 \u0000 <p>Designer precursors for the synthesis of amphetamine-type stimulants pose a significant challenge to law enforcement. The precursors APAAN (α-phenylacetoacetonitrile) and MAPA (methyl α-acetylphenylacetate) became popular in the previous decade and have since been restricted. Recently, a ring-substituted analog of MAPA used for the synthesis of MDMA (3,4-methylenedioxymethamphetamine) was detected, highlighting the potential for criminal misuse of substituted analogs of these designer precursors. Previous research has characterized the impurity profiles of methamphetamine synthesized from APAAN and MAPA. In this study, the impurity profiles of MDMA and PMMA (<i>p</i>-methoxymethamphetamine) synthesized from ring-substituted analogs of APAAN and MAPA were characterized. In addition, byproducts forming from the conversion of <i>p</i>-methyl and <i>p</i>-fluoro analogs of APAAN and MAPA into analogs of P2P were investigated. MDMA was synthesized from 3,4-methylenedioxy-substituted MAPA (methyl α-acetyl-[3,4-methylenedioxyphenyl]acetate, MAMDPA) via sodium cyanoborohydride reductive amination and hydrogenation with platinum oxide and methylamine. Four impurities originating from MAMDPA were detected in MDMA synthesized via reductive amination, all of which are 3,4-methylenedioxy analogs of the impurities detected in methamphetamine synthesized from MAPA. Synthesis of MDMA via the hydrogenation route only produced one characteristic impurity, which, due to its instability under acidic conditions, is not likely to be present in clandestine MDMA hydrochloride samples. PMMA was synthesized via sodium cyanoborohydride reductive amination of MeO-P2P produced from methoxyl-substituted APAAN (α-<i>p-</i>methoxyphenylacetoacetonitrile, APMPAAN). Five impurities were identified as originating from APMPAAN, two of which are proposed to be the most reliable markers for the use of APMPAAN in the synthesis of PMMA.</p>\u0000 </div>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"17 12","pages":"2354-2373"},"PeriodicalIF":2.7,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145022545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"RETRACTION: Voltammetric Determination of Isoproterenol Using Multiwall Carbon Nanotubes-Ionic Liquid Paste Electrode","authors":"","doi":"10.1002/dta.3949","DOIUrl":"10.1002/dta.3949","url":null,"abstract":"<p>\u0000 <b>RETRACTION</b>: <span>A. A. Ensafi</span> and <span>H. Karimi-Maleh</span>, “ <span>Voltammetric Determination of Isoproterenol Using Multiwall Carbon Nanotubes-Ionic Liquid Paste Electrode</span>,” <i>Drug Testing and Analysis</i> <span>3</span>, no. <span>5</span> (<span>2011</span>): <span>325</span>–<span>330</span>, https://doi.org/10.1002/dta.232.</p><p>The above article, published online on 09 February 2011 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement of the journal Editor-in-Chief, Mario Thevis; and John Wiley &amp; Sons Ltd. Following publication, concerns were raised by third parties regarding Figures 1A and 1B. The authors were unable to provide a satisfactory explanation and could not provide the original data. The retraction has been agreed because of concerns that the figures were duplicated and used to represent different materials. This affects the interpretation of the data and results presented.</p><p>The authors disagree with the decision to retract.</p>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"17 10","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://analyticalsciencejournals.onlinelibrary.wiley.com/doi/epdf/10.1002/dta.3949","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144991048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enantiomeric Determination of Medetomidine in Street Drug Samples (August 2024—February 2025) and Implications for Immunoassay Test Strip Analysis","authors":"Edward Sisco,&nbsp;Mónica Ventura,&nbsp;Sarah A. Shuda","doi":"10.1002/dta.3947","DOIUrl":"10.1002/dta.3947","url":null,"abstract":"<div>\u0000 \u0000 <p>Over the last several years, there has been an influx of α₂-agonists into the street drug supply, beginning with the proliferation of xylazine, a potent veterinary sedative. Since 2023, another sedative, medetomidine, has been widely detected. Medetomidine, broadly, encompasses two enantiomers—dexmedetomidine and levomedetomidine—with the dex enantiomer being pharmacologically active and present in human-use pharmaceuticals. In this work, we investigate street drug samples containing medetomidine to better understand the enantiomeric makeup in the illicit supply. Liquid chromatography tandem mass spectrometry (LC–MS/MS) was used to analyze 100 drug product or paraphernalia residue samples. All samples were found to contain a racemic mixture of medetomidine. A subset of samples was analyzed by medetomidine immunoassay test strips, where racemic mixtures were not found to negatively affect results. All samples were also qualitatively analyzed using direct analysis in real time mass spectrometry (DART-MS) to identify commonly co-occurring compounds, which included fentanyl, xylazine, and local anesthetics. Parabens, preservatives found in licit injectable preparations of the drug, were not detected. This work provides a snapshot into the medetomidine makeup of the street drug supply, which needs to be continually monitored given the differences in pharmacology between the two enantiomers.</p>\u0000 </div>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"17 12","pages":"2347-2353"},"PeriodicalIF":2.7,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144991033","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification of Tetrahydrocannabidiol Metabolites in Human Urine","authors":"Willi Schirmer,&nbsp;Isabelle Mösch,&nbsp;Stefan Schürch,&nbsp;Wolfgang Weinmann","doi":"10.1002/dta.3945","DOIUrl":"10.1002/dta.3945","url":null,"abstract":"<p>Tetrahydrocannabidiol (H4CBD) is an emerging semisynthetic cannabinoid, which has been known since 1940. Like hexahydrocannabinol (HHC), it is easily obtained by hydrogenation of available phytocannabinoids, in the case of H4CBD by hydrogenation of cannabidiol (CBD). H4CBD shows a weak affinity for the CB₁ receptor, but it is unclear if H4CBD shows psychoactive properties, as reports from users are divided. Only a few countries have placed H4CBD under their narcotic substance law, for example, France and Switzerland. The aim of this study was to identify human Phase I and II metabolites in urine as potential forensic targets. The H4CBD used for this study was bought from an online store and analyzed beforehand using GC–MS. The Phase I and II metabolites were identified using LC-HR-MS/MS and GC–MS after trimethylsilylation. The found H4CBD metabolites were carboxylated, hydroxylated, and bishydroxylated species and their glucuronides with hydroxylation and carboxylation positions on the alicyclic moiety and on the side chain. The tentatively identified metabolites were the carboxylic acids 5″-COOH-H4CBD and 7-COOH-H4CBD, the hydroxylated metabolites (1<i>R</i>,6<i>R</i>)-OH-H4CBD, (1<i>R</i>,6<i>S</i>)-OH-H4CBD, two epimers of 2″-OH-H4CBD, and both epimers of 7-OH-H4CBD. The identified bishydroxylated metabolites were side-chain hydroxylated derivatives of 7-OH-H4CBD. Various other hydroxylated metabolites were found, but their exact hydroxylation positions could not be determined. Some ESI+ spectra of the metabolites showed very unusual fragmentation patterns, like the loss of both oxygens from the resorcinol moiety with subsequent ring contraction and the appearance of radical cations for Phase II metabolites. These unusual patterns were noticed for H4CBD and its side-chain-altered metabolites.</p>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"17 12","pages":"2333-2346"},"PeriodicalIF":2.7,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://analyticalsciencejournals.onlinelibrary.wiley.com/doi/epdf/10.1002/dta.3945","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144937298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification of Candidate Blood Biomarkers of Recombinant Human Erythropoietin Administration Using Targeted Polar Metabolomics by HILIC-MS/MS","authors":"Olivier Salamin,&nbsp;Lejla Ramic,&nbsp;Raul Nicoli,&nbsp;Serge Rudaz,&nbsp;Davy Guillarme,&nbsp;Tiia Kuuranne","doi":"10.1002/dta.3943","DOIUrl":"10.1002/dta.3943","url":null,"abstract":"<p>Increasing oxygen transport through elevated hemoglobin concentration and red blood cell mass is a key objective of blood doping, commonly achieved via recombinant human erythropoietin (rHuEPO) administration or blood transfusions. While the Athlete Biological Passport (ABP) offers an effective indirect tool for detecting such manipulations, its sensitivity and specificity may be limited, particularly in cases involving microdoses or confounding physiological factors. To address these limitations, the identification of novel biomarkers that complement current ABP markers is essential.</p><p>This study presents a targeted metabolomics approach to discover candidate biomarkers of rHuEPO administration by analyzing polar metabolites in plasma and serum from two administration studies: one involving a single CERA injection, and the other using multiple doses of epoetin delta. Hydrophilic interaction chromatography hyphenated with tandem mass spectrometry enabled the selective and sensitive detection of a panel of polar endogenous metabolites.</p><p>Following data normalization and stringent quality control, generalized least squares models were applied to evidence temporal changes in metabolite signals. Among the most responsive and concordant markers across both studies were hypoxanthine and inosine, which showed significant and marked increases following rHuEPO administration. Notably, the relative increase of these metabolites coincided with the maximum in reticulocyte percentages, reflecting maximal erythropoietic activity. As intermediates in purine metabolism, their increases are likely tied to augmented purine turnover during red blood cell production. These findings suggest that hypoxanthine and inosine are promising candidate biomarkers to complement existing ABP parameters. However, further validation is required to confirm their reliability and applicability within the ABP framework.</p>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"17 12","pages":"2323-2332"},"PeriodicalIF":2.7,"publicationDate":"2025-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://analyticalsciencejournals.onlinelibrary.wiley.com/doi/epdf/10.1002/dta.3943","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144937380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biosynthesis and Identification of Clenbuterol Metabolites in Urine and In Vitro Microsome Incubation Samples Using UHPLC-Q-Exactive Orbitrap Mass Spectrometry: A Comparison Between Human and Bovine Metabolism","authors":"Anuar Gómez-Tagle,&nbsp;Claudia Bressan,&nbsp;Rosa Ventura,&nbsp;Alan Álvarez-Sanchez,&nbsp;Enrique Cardenas-Yong,&nbsp;Benjamín Velasco-Bejarano","doi":"10.1002/dta.3942","DOIUrl":"10.1002/dta.3942","url":null,"abstract":"<p>Clenbuterol (Clb) is a β2-agonist drug included in the list of substances prohibited during and out of competition by the World Anti-Doping Agency (WADA-AMA). Several adverse analytical findings have been detected by accredited WADA laboratories, but athletes often claim that results are due to dietary contamination. In this contribution, bovine microsomal incubation and the excretion of bovine and human urinary metabolites of Clb were analyzed and compared using liquid chromatography electrospray Q-Exactive-Orbitrap mass spectrometry to determine differences in Clb metabolism. Urine samples were processed by solid-phase extraction prior to electrospray analysis in both the positive and negative ion modes. MS/MS experiments were obtained by parallel monitoring reaction (PRM) triggered by an inclusion ions list. The strategy for metabolite identification involved the search for typical biotransformation based on accurate mass shifts using diagnostic fragment ions from the parent drug. This approach successfully identified eight metabolites, including a novel <i>N</i>-methylated form of Clb, reported here for the first time. Additionally, four metabolites found exclusively in bovine urine offer significant potential for further research aimed at distinguishing unintentional doping.</p>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"17 12","pages":"2314-2322"},"PeriodicalIF":2.7,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://analyticalsciencejournals.onlinelibrary.wiley.com/doi/epdf/10.1002/dta.3942","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144937281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Testing for Meldonium, a Doping Agent, in Human Hair","authors":"Pascal Kintz,&nbsp;Jean-Claude Alvarez,&nbsp;Laurie Gheddar","doi":"10.1002/dta.3941","DOIUrl":"10.1002/dta.3941","url":null,"abstract":"<div>\u0000 \u0000 <p>Meldonium has been developed in the 70s in Latvia and is currently used in a limited number of countries for heart-related diseases, such as heart attack, failure, or angina pectoris. Due to its metabolic properties (decrease of lactate production, increase of glycogen use, and protective action again oxidative stress), meldonium has been abused by numerous athletes to enhance their performance. The drug has been prohibited by the World Anti-Doping Agency since 2016 and is on the S4.4.3 list (metabolic modulators) of the prohibited substances at all times. As athletes can challenge their anti-doping violation involving meldonium, there is an interest in testing for it in hair in order to document their pattern of exposure. Such hair application can be complicated to develop, as meldonium has a chemical formula close to an amino acid and presents an ionized fraction, which are limiting factors for drug incorporation into hair. Liquid chromatography coupled to tandem mass spectrometry was used. The drug was extracted from hair after methanol incubation in an ultrasound bath and separation on a BEH HILIC column. Linearity was verified from 0.5 to 100 pg/mg (<i>R</i>² = 0.9943). The limit of detection was 0.1 pg/mg. Although their meldonium regimen was unknown, the drug was identified in the proximal hair segment (0 to 1 cm) of three consumers at 0.7, 6.1, and 17 pg/mg, highlighting for the first time the incorporation in hair of this molecule.</p>\u0000 </div>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"17 12","pages":"2308-2313"},"PeriodicalIF":2.7,"publicationDate":"2025-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144937328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}