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Gabert K, Seheult JN, Meyer MP, Triulzi DJ, Kaplan A. An unusual case of anti-D detection in two consecutive D+ patient samples: Antibody carryover on an automated gel platform. Transfusion 2021; 61:2545-2548. [PMID: 34228353 DOI: 10.1111/trf.16578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 05/17/2021] [Accepted: 06/13/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND Laboratory results can be affected by sample to sample carryover. Carryover of different analytes occurring in automated clinical chemistry, immunology, hematology, and molecular laboratories is well described. However, carryover in a transfusion service laboratory is not reported in medical literature. MATERIALS AND METHODS Immunohematology testing results, demographic data, and clinical data were reviewed on three patients retrospectively from 2015 to 2019. RESULTS Type and screen samples tested on automated gel platform from two D+ patients were affected by anti-D carryover from a patient sample with a very high-titer anti-D. Additional immunohematology and molecular testing confirmed that anti-D in samples of two D+ patients was due to carryover. CONCLUSION A case of anti-D carryover caused false detection of anti-D in two D+ patients. Carryover can have implications for patient management. Transfusion laboratory staff need to be aware of it and investigate any unexpected results further.
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Affiliation(s)
- Kimberly Gabert
- Department of Reference and Transfusion Services, IRL, Vitalant, Pittsburgh, Pennsylvania, USA
| | - Jansen N Seheult
- Division of Transfusion Medicine, Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.,Institution: Vitalant Specialty Laboratories & Therapeutics, Vitalant, Pittsburgh, Pennsylvania, USA
| | - Michael P Meyer
- Department Coagulation Laboratory, Vitalant Specialty Laboratories & Therapeutics, Vitalant, Pittsburgh, Pennsylvania, USA
| | - Darrell J Triulzi
- Division of Transfusion Medicine, Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Alesia Kaplan
- Division of Transfusion Medicine, Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
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2
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Nolte FS. Distributed Model for Molecular Diagnostics. Clin Chem 2019; 66:clinchem.2019.304634. [PMID: 31719036 DOI: 10.1373/clinchem.2019.304634] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 08/02/2019] [Indexed: 11/06/2022]
Affiliation(s)
- Frederick S Nolte
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC.
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3
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Consecutive reactive results in screening of transfusion transmitted infections: Family history of blood donors is also important. Transfus Apher Sci 2019; 58:464-467. [PMID: 31324573 DOI: 10.1016/j.transci.2019.05.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Revised: 05/02/2019] [Accepted: 05/02/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Enzyme linked immunosorbent assay (ELISA) test is used for screening of transfusion transmitted infections (TTI) in blood donors. Consecutive reactive results in ELISA is due to sample/reagent carryover or donor related. In this study we tried to find out the possibilities of family history/close contacts with patients of hepatitis among these consecutive reactive donors. AIM To analyze the consecutive reactive results in ELISA tests for TTI testing on samples of healthy blood donors. MATERIAL AND METHODS A retrospective observational study was conducted from January 2016 to July 2018 in a tertiary care hospital, North India. Consecutive reactive results by fourth generation ELISA for TTIs screening were evaluated for possible reasons. Confirmation tests were not done. Reactive donors were contacted telephonically for relevant history of close contact with infected personnel. RESULTS Out of 53,740 donations 1,061 were reactive for TTIs during our study period. Prevalence of Hepatitis B (HBV), Human Immunodeficiency (HIV) and Hepatitis C (HCV) virus infection in blood donors were 1.27%, 0.20% and 0.50% respectively. Consecutive reactive results for HBV were 9.20% (63/685), for HCV 6.0% (16/266) and nil for HIV. There was no sample carryover in this. Out of 79 consecutive reactive donors 69 donated for same patients and 32 were related with infected patient which are statistically significant (p < 0.0001). DISCUSSION This study recommends that in analysis of consecutive positive results in ELISA along with looking for procedure/sample error, there is also a need to take retrospective history of donors for close contact with infected patients.
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Vidranski V, Franceschi M, Krilić D, Jukić T, Mihaljević I, Kusić Z. Analytical evaluation of the new Seal Autoanalyzer 3 High Resolution for urinary iodine determination. Biochem Med (Zagreb) 2019; 29:bm-29-2-020711. [PMID: 31223253 PMCID: PMC6559621 DOI: 10.11613/bm.2019.020711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Accepted: 05/06/2019] [Indexed: 12/05/2022] Open
Abstract
Introduction The aim of the study was to evaluate the analytical performance of the new colorimetric, automatic analyser, Seal AutoAnalyzer 3 High Resolution (Seal AA3 HR) (Seal Analytical, Wisconsin, USA) for urinary iodine measurement. Materials and methods This study included testing of several analytical features of the method involving: imprecision (within-run %CVr, between-run %CVb and total laboratory precision %CVl), measurement uncertainty, carryover, linearity and method comparison, with 70 urine samples including the measuring range (20 - 700 µg/L). Results Within-run, %CVb and %CVl of two control levels were 2.03% and 3.04%, 0.51% and 2.61%, and 2.09% and 4.01%, respectively. Carryover effect was less than 1%. The linearity was good in the range of urinary iodine values between 60 and 500 µg/L (R2 = 0.99). Good agreement of urinary iodine values was found between manual technique and Seal AA3 HR, using Passing-Bablok regression (y = 7.84 (- 3.00 to 15.29) + 0.95 (0.90 to 1.00) x) and Blant-Altman test. Cusum test for linearity indicates that there is no significant deviation from linearity (P > 0.1). Conclusions The obtained results proved excellent precision, reproducibility and linearity, comparable to the already used, manual method. The New Seal AA3 HR automatic analyser is acceptable for urinary iodine measurement with very good analytical characteristics and can be used for urinary iodine epidemiological studies of the Croatian population.
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Affiliation(s)
- Valentina Vidranski
- Department for Oncology and Nuclear Medicine, University Hospital Center Sestre milosrdnice, Zagreb, Croatia; Faculty of medicine Osijek, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia
| | - Maja Franceschi
- Department for Oncology and Nuclear Medicine, University Hospital Center Sestre milosrdnice, Zagreb, Croatia; Faculty of medicine Osijek, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia
| | - Dražena Krilić
- Department for Oncology and Nuclear Medicine, University Hospital Center Sestre milosrdnice, Zagreb, Croatia
| | - Tomislav Jukić
- Department for Oncology and Nuclear Medicine, University Hospital Center Sestre milosrdnice, Zagreb, Croatia; Faculty of medicine Osijek, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia
| | - Ivan Mihaljević
- Department for Nuclear Medicine and Radiation Protection, University Hospital Center Osijek, Osijek, Croatia; Faculty of medicine Osijek, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia
| | - Zvonko Kusić
- Croatian Academy of Sciences and Arts, Zagreb, Croatia
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5
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Vogeser M, Seger C. Irregular analytical errors in diagnostic testing - a novel concept. Clin Chem Lab Med 2018; 56:386-396. [PMID: 28902615 DOI: 10.1515/cclm-2017-0454] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 07/31/2017] [Indexed: 11/15/2022]
Abstract
BACKGROUND In laboratory medicine, routine periodic analyses for internal and external quality control measurements interpreted by statistical methods are mandatory for batch clearance. Data analysis of these process-oriented measurements allows for insight into random analytical variation and systematic calibration bias over time. However, in such a setting, any individual sample is not under individual quality control. The quality control measurements act only at the batch level. Quantitative or qualitative data derived for many effects and interferences associated with an individual diagnostic sample can compromise any analyte. It is obvious that a process for a quality-control-sample-based approach of quality assurance is not sensitive to such errors. CONTENT To address the potential causes and nature of such analytical interference in individual samples more systematically, we suggest the introduction of a new term called the irregular (individual) analytical error. Practically, this term can be applied in any analytical assay that is traceable to a reference measurement system. For an individual sample an irregular analytical error is defined as an inaccuracy (which is the deviation from a reference measurement procedure result) of a test result that is so high it cannot be explained by measurement uncertainty of the utilized routine assay operating within the accepted limitations of the associated process quality control measurements. SUMMARY The deviation can be defined as the linear combination of the process measurement uncertainty and the method bias for the reference measurement system. Such errors should be coined irregular analytical errors of the individual sample. The measurement result is compromised either by an irregular effect associated with the individual composition (matrix) of the sample or an individual single sample associated processing error in the analytical process. OUTLOOK Currently, the availability of reference measurement procedures is still highly limited, but LC-isotope-dilution mass spectrometry methods are increasingly used for pre-market validation of routine diagnostic assays (these tests also involve substantial sets of clinical validation samples). Based on this definition/terminology, we list recognized causes of irregular analytical error as a risk catalog for clinical chemistry in this article. These issues include reproducible individual analytical errors (e.g. caused by anti-reagent antibodies) and non-reproducible, sporadic errors (e.g. errors due to incorrect pipetting volume due to air bubbles in a sample), which can both lead to inaccurate results and risks for patients.
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Affiliation(s)
- Michael Vogeser
- Institute of Laboratory Medicine, University Hospital, LMU Munich, Germany, Marchioninistr. 15, 81377 München, Germany
| | - Christoph Seger
- labormedizinisches zentrum Dr. Risch, Lagerstrasse 30, 9470 Buchs SG, Switzerland
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Nutrients in Energy and One-Carbon Metabolism: Learning from Metformin Users. Nutrients 2017; 9:nu9020121. [PMID: 28208582 PMCID: PMC5331552 DOI: 10.3390/nu9020121] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 01/31/2017] [Accepted: 02/07/2017] [Indexed: 02/07/2023] Open
Abstract
Metabolic vulnerability is associated with age-related diseases and concomitant co-morbidities, which include obesity, diabetes, atherosclerosis and cancer. Most of the health problems we face today come from excessive intake of nutrients and drugs mimicking dietary effects and dietary restriction are the most successful manipulations targeting age-related pathways. Phenotypic heterogeneity and individual response to metabolic stressors are closely related food intake. Understanding the complexity of the relationship between dietary provision and metabolic consequences in the long term might provide clinical strategies to improve healthspan. New aspects of metformin activity provide a link to many of the overlapping factors, especially the way in which organismal bioenergetics remodel one-carbon metabolism. Metformin not only inhibits mitochondrial complex 1, modulating the metabolic response to nutrient intake, but also alters one-carbon metabolic pathways. Here, we discuss findings on the mechanism(s) of action of metformin with the potential for therapeutic interpretations.
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Frégeau CJ, Yensen C, Elliott J, Fourney RM. Optimized Configuration of Fixed-Tip Robotic Liquid-Handling Stations for the Elimination of Biological Sample Cross-Contamination. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.jala.2007.08.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Robotic liquid-handling stations (RLHSs) are the mainstay of high-throughput biomedical/forensic DNA sample processing facilities. These liquid-handling systems can be alternatively tooled with either disposable or fixed-tip pipetting heads. The use of disposable tips is often perceived as the best tip configuration to eliminate cross-contamination between biological samples processed on liquid-handling stations. However, this suppression can be effectively achieved on instruments equipped with fixed tips with optimally designed tip wash station (WS) configurations. Fixed-tip instruments offer many significant sample processing advantages with respect to precision, pipetting of liquids that may contain aggregates, and operational cost. This report discusses how cross-contamination suppression was achieved for the reliable processing of forensic casework samples on specially configured fixed-tip TECAN Genesis RSP/Freedom EVO RLHSs. A critical analysis of the major components involved in tip washing, as well as the specifications of a redesigned tip-washing routine that increases wash effectiveness and significantly reduces processing time and cost is also presented.
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Affiliation(s)
| | - Craig Yensen
- Royal Canadian Mounted Police, Ottawa, Ontario, Canada
| | - Jim Elliott
- Royal Canadian Mounted Police, Ottawa, Ontario, Canada
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8
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Carryover: More than just a major hangover for the clinical laboratory. Clin Biochem 2016; 49:735-6. [DOI: 10.1016/j.clinbiochem.2016.05.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 05/20/2016] [Indexed: 11/23/2022]
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Füzéry AK, Levin J, Chan MM, Chan DW. Translation of proteomic biomarkers into FDA approved cancer diagnostics: issues and challenges. Clin Proteomics 2013; 10:13. [PMID: 24088261 PMCID: PMC3850675 DOI: 10.1186/1559-0275-10-13] [Citation(s) in RCA: 274] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 08/31/2013] [Indexed: 12/22/2022] Open
Abstract
Tremendous efforts have been made over the past few decades to discover novel cancer biomarkers for use in clinical practice. However, a striking discrepancy exists between the effort directed toward biomarker discovery and the number of markers that make it into clinical practice. One of the confounding issues in translating a novel discovery into clinical practice is that quite often the scientists working on biomarker discovery have limited knowledge of the analytical, diagnostic, and regulatory requirements for a clinical assay. This review provides an introduction to such considerations with the aim of generating more extensive discussion for study design, assay performance, and regulatory approval in the process of translating new proteomic biomarkers from discovery into cancer diagnostics. We first describe the analytical requirements for a robust clinical biomarker assay, including concepts of precision, trueness, specificity and analytical interference, and carryover. We next introduce the clinical considerations of diagnostic accuracy, receiver operating characteristic analysis, positive and negative predictive values, and clinical utility. We finish the review by describing components of the FDA approval process for protein-based biomarkers, including classification of biomarker assays as medical devices, analytical and clinical performance requirements, and the approval process workflow. While we recognize that the road from biomarker discovery, validation, and regulatory approval to the translation into the clinical setting could be long and difficult, the reward for patients, clinicians and scientists could be rather significant.
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Affiliation(s)
- Anna K Füzéry
- Department of Pathology, Johns Hopkins University, School of Medicine, Baltimore, MD 21287, USA.
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10
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Schmotzer CL, Zhou L. Risk of false positive hepatitis C virus RNA due to sample to sample carryover on an automated hematology analyzer. Clin Chem Lab Med 2012; 50:2235-6. [DOI: 10.1515/cclm-2012-0274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Accepted: 06/08/2012] [Indexed: 11/15/2022]
Affiliation(s)
- Christine L. Schmotzer
- Department of Pathology, University Hospitals Case Medical Center, Cleveland , OH , United States of America
| | - Lan Zhou
- Department of Pathology, University Hospitals Case Medical Center, Cleveland , OH , United States of America
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11
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Sample carryover in PT-INR determination is it an issue in Oral Anticoagulant Therapy control? Thromb Res 2010; 127:279-81. [PMID: 21129767 DOI: 10.1016/j.thromres.2010.10.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Revised: 10/07/2010] [Accepted: 10/20/2010] [Indexed: 11/21/2022]
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Weibel R, Iten M, König I, Beckbissinger R, Benthien T, Hälg W, Ingenhoven N, Lehnert A, Oeltjen L, Zaborosch C. Development of Standard Test Procedures for Quantifying Carry over from Fixed Pipetting Tips in Liquid-Handling Systems. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.jala.2009.08.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Robotic liquid-handling systems using fixed reusable pipetting tips are used not only in fully integrated in vitro clinical diagnostic analyzers, but also in open platform robotic liquid-handling systems. These are not confined to particular diagnostic assays, as customers adapt a large variety of assays on these platforms. One major problem with the use of fixed, reusable tips is the carry over (CO) of analyte from sample to sample. Despite widespread use of fixed tips in open platform systems, systematic studies on procedures to quantify CO for analytes other than nucleic acids are missing. In a consortium with three liquid-handling system suppliers and one coating specialist, we developed test procedures for the quantification of CO. The procedures were standardized and tested with the analytes fluorescein, immunoglobulin G, and hepatitis B surface antigen as model substances for small organic molecules, antibodies, and complex biomolecules. The test procedures allow the reproducible quantification of the CO with intra- and interassay precisions of less than 6% coefficient of variation. They were used to investigate the effect of different tip coatings on the CO of the three analytes. Fluoropolymers, inorganic-organic nanocomposites, sodium-silicate glass, titanium dioxide, and silicone resins, which are used in special applications, showed only small differences in CO. The CO test procedures can be easily transferred to different liquid-handling systems and used with different analytes.
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Affiliation(s)
- Roland Weibel
- Zurich University of Applied Sciences, Institute of Chemistry and Biological Chemistry, Wädenswil, Switzerland
| | - Miriam Iten
- Zurich University of Applied Sciences, Institute of Chemistry and Biological Chemistry, Wädenswil, Switzerland
| | - Iwo König
- Zurich University of Applied Sciences, Institute of Chemistry and Biological Chemistry, Wädenswil, Switzerland
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Reduction of Carry over in Liquid-Handling Systems with a Decontamination Step Integrated in the Washing Procedure. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.jala.2010.05.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Robotic liquid-handling systems can be equipped with disposable pipetting tips or fixed reusable pipetting tips. The use of disposable tips is perceived as the best option to avoid carry over (CO) of analyte from sample to sample. We recently developed standardized CO test procedures that allow precise and reproducible quantification of CO for fixed reusable tips. We used these test procedures to reduce CO of the analytes fluorescein, IgG, and hepatitis B surface antigen (HBsAg) to minimal levels. Variations of washing intensity, using water as a washing solution, did not lower CO below acceptable target levels. These target levels would preclude a false-positive detection of IgG and HBsAg in human serum when a negative sample is measured subsequent to a sample with a high analyte concentration. We therefore integrated a decontamination step into the washing procedure. Screening of 12 decontamination solutions showed that sodium hypochlorite solution was very efficient in reducing CO. Optimization led to a final washing routine in which tips are exposed for 0.2 s to 0.17 M NaOCI and subsequently rinsed with 2 mL of water to remove any remaining decontaminant solution. The washing procedure only takes 15 s and is thus suitable for high-throughput applications. The procedure was able to lower CO of IgG and HBsAg in human sera below relevant levels. The decontamination step with hypochlorite can easily be integrated into different liquid-handling systems and is likely to be effective against CO of most proteins and peptides.
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Abstract
Most steroid disorders of the adrenal cortex come to clinical attention in childhood and in order to investigate these problems, there are many challenges to the laboratory which need to be appreciated to a certain extent by clinicians. The analysis of sex steroids in biological fluids from neonates, over adrenarche and puberty present challenges of specificities and concentrations often in small sample sizes. Different reference ranges are also needed for interpretations. For around 40 years, quantitative assays for the steroids and their regulatory peptide hormones have been possible using immunoassay techniques. Problems are recognised and this review aims to summarise the benefits and failings of immunoassays and introduce where tandem mass spectrometry is anticipated to meet the clinical needs for steroid analysis in paediatric endocrine investigations. It is important to keep a dialogue between clinicians and the laboratory, especially when any laboratory result does not make sense in the clinical investigation.
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Affiliation(s)
- John W Honour
- Clinical Biochemistry, University College London Hospitals, London, England.
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15
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Frégeau CJ, Marc Lett C, Elliott J, Yensen C, Fourney RM. Automated Processing of Forensic Casework Samples Using Robotic Workstations Equipped with Nondisposable Tips: Contamination Prevention. J Forensic Sci 2008; 53:632-51. [DOI: 10.1111/j.1556-4029.2008.00697.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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16
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Bakhtiar R, Majumdar TK. Tracking problems and possible solutions in the quantitative determination of small molecule drugs and metabolites in biological fluids using liquid chromatography–mass spectrometry. J Pharmacol Toxicol Methods 2007; 55:262-78. [PMID: 17174577 DOI: 10.1016/j.vascn.2006.10.002] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2006] [Accepted: 10/30/2006] [Indexed: 11/20/2022]
Abstract
During the last decade, quantification of low molecular weight molecules using liquid chromatography-tandem mass spectrometry in biological fluids has become a common procedure in many preclinical and clinical laboratories. This overview highlights a number of issues involving "small molecule drugs", bioanalytical liquid chromatography-tandem mass spectrometry, which are frequently encountered during assay development. In addition, possible solutions to these issues are proposed with examples in some of the case studies. Topics such as chromatographic peak shape, carry-over, cross-talk, standard curve non-linearity, internal standard selection, matrix effect, and metabolite interference are presented. Since plasma is one of the most widely adopted biological fluid in drug discovery and development, the focus of this discussion will be limited to plasma analysis. This article is not intended to be a comprehensive overview and readers are encouraged to refer to the citations herein.
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Affiliation(s)
- Ray Bakhtiar
- Department of Drug Metabolism, Merck Research Laboratories, Rahway, NJ 07065, USA.
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