Journal of Mass Spectrometry and Advances in the Clinical Lab最新文献

{"title":"Therapeutic drug monitoring of clozapine in human serum by high-throughput paper spray mass spectrometry","authors":"A. Saatchi ,&nbsp;T.M. Zarkovic ,&nbsp;S.A. Borden ,&nbsp;J. Palaty ,&nbsp;C.G. Gill","doi":"10.1016/j.jmsacl.2024.02.003","DOIUrl":"10.1016/j.jmsacl.2024.02.003","url":null,"abstract":"<div><h3>Introduction</h3><p>Monitoring the atypical antipsychotic drug clozapine is crucial to ensure patient safety. This article showcases a high-throughput analytical method for measuring clozapine and its primary metabolite norclozapine (N-desmethylclozapine) in serum using paper spray mass spectrometry (PS-MS).</p></div><div><h3>Objectives</h3><p>This study aimed to assess the viability of a PS-MS method for the rapid measurement of clozapine and norclozapine in human serum samples as an alternative to liquid chromatography mass spectrometry (LC-MS).</p></div><div><h3>Methods</h3><p>Serum samples were processed by protein precipitation followed by deposition of the supernatant containing labelled internal standards onto paper spray substrates mounted in cartridges. Analytes were then analyzed using a triple quadrupole mass spectrometer equipped with a commercial paper spray ionization source. The results obtained from the patient samples were compared to those from a validated LC-MS assay.</p></div><div><h3>Results</h3><p>PS-MS calibrations for clozapine and norclozapine were linear (R² &gt; 0.99) over five days. Between-run precision was below 8 %, and within-run precision did not exceed 10 %. When compared to a validated LC-MS method, the mean bias for 39 patient samples was −9% for clozapine and −1% for norclozapine, with no outliers. Mass spectrometry ion ratio comparisons indicated no interference for patient samples above the lower limit of quantification. There was less than 7 % change in the measured concentrations of both analytes over five days for samples dried on paper substrates. Notably, virtually no maintenance of the MS source was required during this study.</p></div><div><h3>Conclusion</h3><p>This study illustrates the potential of PS-MS for serum drug monitoring in the clinical laboratory.</p></div>","PeriodicalId":52406,"journal":{"name":"Journal of Mass Spectrometry and Advances in the Clinical Lab","volume":"32 ","pages":"Pages 41-46"},"PeriodicalIF":2.2,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667145X24000166/pdfft?md5=801455da959bf187a1238dd67f5e64b1&pid=1-s2.0-S2667145X24000166-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139886849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electrospray triple quadrupole mass spectrometry guides pathologists to suggest appropriate molecular testing in the identification of rare hemoglobin variants","authors":"Deepalakshmi Dakshinamoorthy Putchen ,&nbsp;Athira Nambiar ,&nbsp;Aswathy Ashok Menon ,&nbsp;Ananthvikas Jayaram ,&nbsp;Sujay Ramaprasad","doi":"10.1016/j.jmsacl.2024.01.005","DOIUrl":"https://doi.org/10.1016/j.jmsacl.2024.01.005","url":null,"abstract":"<div><h3>Background</h3><p>The presumptive diagnosis of hemoglobinopathies relies on routine tests such as Complete Blood Count (CBC), peripheral blood smear, Liquid Chromatography (LC), and Capillary Electrophoresis (CE), along with clinical findings. Pathologists suggest molecular sequencing of HBA and HBB genes to correlate blood picture with clinical findings in order to identify unknown rare haemoglobin (Hb) variants or variants that coelute with Hb. This paper presents a low-resolution mass spectrometry (MS)-based method for presumptive identification of variants that eluted in zone 12 of CE, followed by molecular sequencing of the HBB gene for a definitive diagnosis of hemoglobinopathies.</p></div><div><h3>Methods</h3><p>Eight patient samples with a variant peak in zone 12 of CE (Sebia) were analyzed using MS. The mass-to-charge ratio (<em>m</em>/<em>z</em>) observed was deconvoluted to determine the mass of Hb variants. The β variants were subsequently confirmed through molecular sequencing.</p></div><div><h3>Results</h3><p>Based on the intact mass of the variants, there were two samples of the α variant (α + 58 Da and α + 44 Da), and six samples of the β variant. Out of these six β variant samples, three were the β + 58 Da variant, and three were the β + 30 Da variant. By correlating the intact mass information with the CE pattern and considering the ethnicity of the patients, it was presumed that the α variants were HbJ Meerut (α + 58 Da, x-axis 102) and HbJ Paris-I (α + 44 Da, x-axis 80). Molecular analysis confirmed the identity of β variants as Hb Rambam/HbJ Cambridge, HbJ Bangkok (+58 Da), and Hb Hofu (+30 Da).</p></div><div><h3>Conclusion</h3><p>The mass information of Hb variants obtained using Electrospray triple quadrupole MS assists pathologists in recommending the appropriate molecular sequencing for identifying unknown variants.</p></div>","PeriodicalId":52406,"journal":{"name":"Journal of Mass Spectrometry and Advances in the Clinical Lab","volume":"32 ","pages":"Pages 18-23"},"PeriodicalIF":2.2,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667145X24000051/pdfft?md5=8b5221f986e6df9a3d2bb87d60ad5265&pid=1-s2.0-S2667145X24000051-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139718620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A validated liquid chromatography-tandem mass spectrometry assay for the analysis of isoniazid and its metabolite acetyl-isoniazid in urine","authors":"Sydwell Poulo Maputla,&nbsp;Willem Van Dalen,&nbsp;Anton Joubert,&nbsp;Jennifer Norman,&nbsp;Sandra Castel,&nbsp;Marthinus van der Merwe,&nbsp;Lubbe Wiesner","doi":"10.1016/j.jmsacl.2024.02.001","DOIUrl":"https://doi.org/10.1016/j.jmsacl.2024.02.001","url":null,"abstract":"<div><h3>Introduction</h3><p>Isoniazid (INH) is one of the most effective and potent first-line anti-tubercular drug. INH is also effectively administered as a preventative monotherapy and has been shown to significantly reduce TB incidence. INH is primarily metabolised to acetyl-isoniazid (AcINH) in the liver. AcINH is mainly excreted in urine presenting as a target for monitoring adherence to INH therapy.</p></div><div><h3>Objective</h3><p>The study aimed to develop and fully validate a bioanalytical method using liquid chromatography-tandem mass spectrometry for the quantification of INH and AcINH in human urine.</p></div><div><h3>Methods</h3><p>The samples were prepared using solid phase extraction, with the internal standards isoniazid-d4 and acetyl-isoniazid-d4 being used. The extracts were chromatographed on an Atlantis T3 analytical column with an isocratic mobile phase. For detection, a AB Sciex™ API 5500 triple quadrupole mass spectrometer was used at unit resolution in the multiple reaction monitoring mode, following positive electrospray ionization.</p></div><div><h3>Results</h3><p>The analytical method demonstrated sufficient sensitivity, as indicated by average signal-to-noise ratios of 7.07 and 6.23 at the lower limit of quantification for INH and AcINH, respectively. Validation was performed over three consecutive batches, demonstrating accuracy, precision, and overall robustness based on peak area ratios within the analytical range of 0.234–30.0 µg/mL for both INH and AcINH. All required validation experiments were assessed and met the acceptance criteria guidelines of the US Food and Drug Administration and European Medicines Agency. The validated method was utilized to measure concentrations of AcINH in urine as a means of assessing adherence to the intake of isoniazid in order to prevent TB infection during a phase III open-label multicenter trial.</p></div><div><h3>Conclusion</h3><p>A bioanalytical method was developed and fully validated for quantifying isoniazid (INH) and acetyl-isoniazid (AcINH) in 100 µL of human urine.</p></div>","PeriodicalId":52406,"journal":{"name":"Journal of Mass Spectrometry and Advances in the Clinical Lab","volume":"32 ","pages":"Pages 11-17"},"PeriodicalIF":2.2,"publicationDate":"2024-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667145X24000087/pdfft?md5=28af3c5a99da213452fbdd600aa4ce94&pid=1-s2.0-S2667145X24000087-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139709929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Infliximab Therapeutic monitoring by tryptic peptide LC-MS/MS method improvements lead to improved accuracy with decreased imprecision and turnaround time","authors":"Paula M. Ladwig,&nbsp;Ann L. Rivard,&nbsp;Alex Barbeln,&nbsp;Anthony Maus,&nbsp;David L. Murray,&nbsp;Melissa R. Snyder,&nbsp;Maria A.V. Willrich","doi":"10.1016/j.jmsacl.2024.01.007","DOIUrl":"10.1016/j.jmsacl.2024.01.007","url":null,"abstract":"<div><h3>Introduction</h3><p>Therapeutic drug monitoring of infliximab has become the standard of care for inflammatory bowel disease in the setting of loss of response to therapy, and occasionally in proactive therapy personalization. Measurement of infliximab by tryptic peptide HPLC-MS/MS has been available since 2015, mostly in reference laboratories.</p></div><div><h3>Objectives</h3><p>Here, we present method improvements to our original published method leading to a more efficient, robust, and high throughput tryptic peptide HPLC-MS/MS assay for infliximab quantitation.</p></div><div><h3>Methods</h3><p>Deidentified residual serum samples submitted for clinical testing were used for method comparison and infliximab was spiked into normal human serum for performance studies. Improvements included the addition of a stable isotope labeled full length infliximab internal standard (IS) replacing a surrogate IS, and immunoenrichment using Melon Gel for immunoglobulins replacing the saturated ammonium sulfate precipitation. Digestion and chromatography were optimized, and automation was added. The method improvements were validated to include precision, accuracy, reportable range, linearity, and analytical sensitivity.</p></div><div><h3>Results</h3><p>The digestion time was reduced from overnight to 1 h. The assay analytical measuring range (AMR) remained the same throughout improvements, 1–100 µg/mL, with linearity of 0.98x + 0.50, R² = 1.00. Intra- and inter-assay imprecision were less than 5 % CV at four different concentrations. Accuracy was assessed with 106 patients within the AMR; Passing-Bablok Regression yielded a slope of 1.00 and a y-intercept of 0.25. Turnaround time was reduced by 1 day, and imprecision of three levels of quality control trended down after new method implementation.</p></div><div><h3>Conclusions</h3><p>Method improvements including automation have allowed for assay completion in half a day, improving robustness and turnaround time.</p></div>","PeriodicalId":52406,"journal":{"name":"Journal of Mass Spectrometry and Advances in the Clinical Lab","volume":"32 ","pages":"Pages 24-30"},"PeriodicalIF":2.2,"publicationDate":"2024-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667145X24000075/pdfft?md5=0c58d3c575ab46fb712891706560a876&pid=1-s2.0-S2667145X24000075-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139879774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How mass spectrometry revolutionized newborn screening","authors":"David S. Millington","doi":"10.1016/j.jmsacl.2024.01.006","DOIUrl":"https://doi.org/10.1016/j.jmsacl.2024.01.006","url":null,"abstract":"<div><p>This article offers a personal account of a remarkable journey spanning over 30 years of applied mass spectrometry in a clinical setting. It begins with the author's inspiration from a clinician's story of rescuing a child from near death with a revolutionary therapeutic intervention. Motivated by this experience, the author delved into the field of chemistry and mass spectrometry to solve an analytical challenge. The breakthrough came with the development of the first front-line diagnostic test performed by MS/MS, which focused on analyzing acylcarnitines to detect and diagnose inherited disorders related to fatty acid and branched-chain amino acid catabolism. Building upon this success, the author expanded the application of the method to dried blood spots, incorporating additional analytical components such as essential amino acids. The result was a groundbreaking multiplex assay capable of screening newborns for more than 30 inherited metabolic conditions with just one test. This novel approach laid the foundation for a targeted metabolomics platform that facilitated the identification of new animal models of metabolic disease through screening the offspring of genetically modified adults. The development and utilization of MS/MS with UPLC has led to the creation of new assays for biomarkers of metabolic disease, benefiting both the diagnosis and therapeutic monitoring of these conditions. The article provides compelling examples from the author's laboratory, highlighting the value and vast applications of these methods in the field of metabolic disease research.</p></div>","PeriodicalId":52406,"journal":{"name":"Journal of Mass Spectrometry and Advances in the Clinical Lab","volume":"32 ","pages":"Pages 1-10"},"PeriodicalIF":2.2,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667145X24000063/pdfft?md5=29e3b0233e687377f97654e19a9de43a&pid=1-s2.0-S2667145X24000063-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139675419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bioanalysis of bedaquiline in human plasma by liquid chromatography-tandem mass spectrometry: Application to pharmacokinetic study","authors":"Viritha Bezawada ,&nbsp;Padma Mogili ,&nbsp;Srinivasa Rao Polagani ,&nbsp;Sireesha Dodda","doi":"10.1016/j.jmsacl.2024.01.001","DOIUrl":"https://doi.org/10.1016/j.jmsacl.2024.01.001","url":null,"abstract":"<div><h3>Introduction</h3><p>A sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for estimation of bedaquiline (BDQ) in human plasma using the deuterated analogue of the analyte, bedaquiline-d6 (BDQ-d6) as the internal standard.</p></div><div><h3>Methods</h3><p>The plasma sample of 50 µL was extracted by liquid–liquid extraction using methyl tertiary butyl ether (MTBE). The separation was achieved on Zodiac C₁₈ (50 x 4.6 mm, 5 µm) column with a mobile phase consisting of methanol and 5 mM ammonium formate in 0.1 % formic acid (w/v) (90:10, v/v) at a flow rate of 1.0 mL/min. Protonated analyte and internal standard were detected on a triple quadrupole mass spectrometer using multiple reaction monitoring (MRM) mode.</p></div><div><h3>Results</h3><p>The linearity of the method was established in the concentration range of 5–––1800 ng/mL with correlation coefficient, r² ≥ 0.99. All the validated parameters were found well within the limits.</p></div><div><h3>Discussion</h3><p>The method was applied for the first time to evaluate the pharmacokinetic parameters after single oral dose of BDQ 100 mg under fed conditions in healthy human volunteers, and the results were further authenticated by incurred sample reanalysis.</p></div>","PeriodicalId":52406,"journal":{"name":"Journal of Mass Spectrometry and Advances in the Clinical Lab","volume":"31 ","pages":"Pages 27-32"},"PeriodicalIF":2.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667145X24000014/pdfft?md5=ff1b006fbe489d9590a4699210ba7696&pid=1-s2.0-S2667145X24000014-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139503577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development and validation of a multiplexed LC-MS/MS ketone body assay for clinical diagnostics","authors":"Robin H.J. Kemperman ,&nbsp;Rebecca D. Ganetzky ,&nbsp;Stephen R. Master","doi":"10.1016/j.jmsacl.2024.01.004","DOIUrl":"10.1016/j.jmsacl.2024.01.004","url":null,"abstract":"<div><h3>Objectives</h3><p>Ketone bodies (KBs) serve as important energy sources that spare glucose, providing the primary energy for cardiac muscle, skeletal muscle during aerobic exercise, and the brain during periods of catabolism. The levels and relationships between the KBs are critical indicators of metabolic health and disease. However, challenges in separating isomeric KBs and concerns about sample stability have previously limited their clinical measurement.</p></div><div><h3>Methods</h3><p>A novel 6.5-minute liquid chromatography-mass spectrometry-based assay was developed, enabling the precise measurement of alpha-, beta- and gamma-hydroxybutyrate, beta-hydroxyisobutyrate, and acetoacetate. This method was fully validated for human serum and plasma samples by investigating extraction efficiency, matrix effects, accuracy, recovery, intra- and inter-precision, linearity, lower limit of quantitation (LLOQ), carryover, specificity, stability, and more. From 107 normal samples, reference ranges were established for all analytes and the beta-hydroxybutyrate/acetoacetate ratio.</p></div><div><h3>Results</h3><p>All five analytes were adequately separated chromatographically. An extraction efficiency between 80 and 120 % was observed for all KBs. Accuracy was evaluated through spike and recovery using 10 random patient samples, with an average recovery of 85–115 % for all KBs and a coefficient of variation of ≤ 3 %. Coefficients of variation for intra- and inter-day imprecision were &lt; 5 %, and the total imprecision was &lt; 10 %. No significant interferences were observed. Specimens remained stable for up to 6 h on ice or 2 h at room temperature.</p></div><div><h3>Conclusions</h3><p>The developed method is highly sensitive and robust. It has been validated for use with human serum and plasma, overcoming stability concerns and providing a reliable and efficient quantitative estimation of ketone bodies.</p></div>","PeriodicalId":52406,"journal":{"name":"Journal of Mass Spectrometry and Advances in the Clinical Lab","volume":"31 ","pages":"Pages 49-58"},"PeriodicalIF":2.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667145X2400004X/pdfft?md5=ecb251e99bcd8539ebb37c657c813fcf&pid=1-s2.0-S2667145X2400004X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139639230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A high-throughput LC-MS/MS assay for piperaquine from dried blood spots: Improving malaria treatment in resource-limited settings","authors":"Daniel Blessborn ,&nbsp;Natpapat Kaewkhao ,&nbsp;Joel Tarning","doi":"10.1016/j.jmsacl.2023.12.004","DOIUrl":"https://doi.org/10.1016/j.jmsacl.2023.12.004","url":null,"abstract":"<div><h3>Background</h3><p>Malaria is a parasitic disease that affects many of the poorest economies, resulting in approximately 241 million clinical episodes and 627,000 deaths annually. Piperaquine, when administered with dihydroartemisinin, is an effective drug against the disease. Drug concentration measurements taken on day 7 after treatment initiation have been shown to be a good predictor of therapeutic success with piperaquine. A simple capillary blood collection technique, where blood is dried onto filter paper, is especially suitable for drug studies in remote areas or resource-limited settings or when taking samples from children, toddlers, and infants.</p></div><div><h3>Methods</h3><p>Three 3.2 mm discs were punched out from a dried blood spot (DBS) and then extracted in a 96-well plate using solid phase extraction on a fully automated liquid handling system. The analysis was performed using LC-MS/MS with a calibration range of 3 – 1000 ng/mL.</p></div><div><h3>Results</h3><p>The recovery rate was approximately 54–72 %, and the relative standard deviation was below 9 % for low, middle and high quality control levels. The LC-MS/MS quantification limit of 3 ng/mL is sensitive enough to detect piperaquine for up to 4–8 weeks after drug administration, which is crucial when evaluating recrudescence and drug resistance development. While different hematocrit levels can affect DBS drug measurements, the effect was minimal for piperaquine.</p></div><div><h3>Conclusion</h3><p>A sensitive LC-MS/MS method, in combination with fully automated extraction in a 96-well plate format, was developed and validated for the quantification of piperaquine in DBS. The assay was implemented in a bioanalytical laboratory for processing large-scale clinical trial samples.</p></div>","PeriodicalId":52406,"journal":{"name":"Journal of Mass Spectrometry and Advances in the Clinical Lab","volume":"31 ","pages":"Pages 19-26"},"PeriodicalIF":2.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667145X23000421/pdfft?md5=cdb560cd35ba8072bfcd7a8f31c71e9d&pid=1-s2.0-S2667145X23000421-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139099707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An LC-MS/MS-based platform for the quantification of multiple amyloid beta peptides in surrogate cerebrospinal fluid","authors":"Merve Oztug,&nbsp;Bilgin Vatansever,&nbsp;Gonca Altin,&nbsp;Muslum Akgoz,&nbsp;Suleyman Z. Can","doi":"10.1016/j.jmsacl.2024.01.002","DOIUrl":"https://doi.org/10.1016/j.jmsacl.2024.01.002","url":null,"abstract":"<div><h3>Introduction</h3><p>The accurate quantification of amyloid beta (Aβ) peptides in cerebrospinal fluid (CSF) is crucial for Alzheimer's disease (AD) research, particularly in terms of preclinical and biomarker studies. Traditional methods, such as the enzyme-linked immunosorbent assay (ELISA), have limitations. These include high costs, labor intensity, lengthy processes, and the possibility of cross-reactivity.</p></div><div><h3>Objectives</h3><p>The primary objectives of this research were twofold: to comprehensively characterize Aβ peptides and to develop a reliable and accurate method for the simultaneous quantification of Aβ 1–40 and Aβ 1–42 peptides in surrogate CSF that is traceable to the International System of Units (SI).</p></div><div><h3>Methods</h3><p>We developed a novel method that combined solid phase extraction (SPE) with isotope dilution liquid chromatography/tandem mass spectrometry (ID-LC/MSMS). SPE was employed to efficiently eliminate matrix interferences, while [15N] Aβ1-40 and [15N] Aβ1-42 served as internal standards to improve accuracy. In addition, we introduced Peptide Impurity Corrected Amino Acid Analysis (PICAA) to ensure traceability to the SI and reliable quantification of Aβ peptides.</p></div><div><h3>Results</h3><p>The developed platform demonstrated a linear calibration range of 300–20000 pg/ml for both Aβ1-42 and Aβ1-40 peptides, accompanied by strong correlation coefficients greater than 0.995. Quality Control (QC) samples demonstrated an accuracy of at least 90.0 %.</p></div><div><h3>Conclusion</h3><p>The enhanced specificity and flexibility of the developed platform potentially have implications for Alzheimer's disease diagnosis and future investigations of novel Aβ peptide biomarkers.</p></div>","PeriodicalId":52406,"journal":{"name":"Journal of Mass Spectrometry and Advances in the Clinical Lab","volume":"31 ","pages":"Pages 40-48"},"PeriodicalIF":2.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667145X24000026/pdfft?md5=5be4e78996c7c16238efa4dcec36f6b3&pid=1-s2.0-S2667145X24000026-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139549479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Therapeutic drug monitoring of glycopeptide antimicrobials: An overview of liquid chromatography-tandem mass spectrometry methods","authors":"Alessia Cafaro ,&nbsp;Sebastiano Barco ,&nbsp;Federica Pigliasco ,&nbsp;Chiara Russo ,&nbsp;Marcello Mariani ,&nbsp;Alessio Mesini ,&nbsp;Carolina Saffioti ,&nbsp;Elio Castagnola ,&nbsp;Giuliana Cangemi","doi":"10.1016/j.jmsacl.2023.12.003","DOIUrl":"10.1016/j.jmsacl.2023.12.003","url":null,"abstract":"<div><p>Therapeutic drug monitoring (TDM) is a critical clinical tool used to optimize the safety and effectiveness of drugs by measuring their concentration in biological fluids. These fluids are primarily plasma or blood. TDM, together with real-time dosage adjustment, contributes highly to the successful management of glycopeptide antimicrobial therapies. Understanding pharmacokinetic/pharmacodynamic (PK/PD) properties is vital for optimizing antimicrobial therapies, as the efficacy of these therapies depends on both the exposure of the patient to the drug (PK) and pharmacodynamic (PD) parameters such as the in vitro estimated minimum drug concentration that inhibits bacterial growth (MIC). Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) is widely recognized as the gold standard for measuring small molecules, such as antibiotics. This review provides a comprehensive overview of LC-MS/MS methods available for TDM of glycopeptide antibiotics, including vancomycin, teicoplanin, dalbavancin, oritavancin, and telavancin.</p></div>","PeriodicalId":52406,"journal":{"name":"Journal of Mass Spectrometry and Advances in the Clinical Lab","volume":"31 ","pages":"Pages 33-39"},"PeriodicalIF":2.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667145X23000408/pdfft?md5=4cbaef25bba910aaf200989c874bec54&pid=1-s2.0-S2667145X23000408-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139012527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}