Clinical chemistry最新文献

{"title":"A-166 Role of Interleukins (2, 6, 10) and Serum Beta-2 Microglobulin (Sß2M) in Chronic Lymphocytic Leukemia","authors":"Sudhahar Tamizhan, Rupali Bains, Manisha Naithani, Uttam Nath","doi":"10.1093/clinchem/hvaf086.161","DOIUrl":"https://doi.org/10.1093/clinchem/hvaf086.161","url":null,"abstract":"Background Chronic lymphocytic leukemia (CLL) remains a challenging disease to manage due to its heterogeneous nature and the lack of clarity regarding prognostic markers. This study aimed to clarify cytokine behavior in different stages (Binet and Modified Rai staging) and phases of CLL, particularly focusing on T helper cell dynamics, and investigate their potential as prognostic biomarkers Methods Serum samples from 70 participants were analyzed for levels of cytokines Interleukin IL-2, IL-6, IL-10, and serum beta2 microglobulin (Sß2M) using Sandwich ELISA and Chemiluminescence immunoassay methods. p-value less than 0.05 were considered statistically significant. Ethical approval number: IEC No. AIIMS/IEC/21/700 dated 24/12/2021 Results In present study, 70 CLL patients were included. Median age recorded as 62 years. The proportion of the disease was 2.45 times higher in males. According to Modified Rai and Binet staging, the study participants were classified into low, moderate, or high risk as 17%, 37%, 46%, and 30%, 26%, and 44%, respectively. The mean levels of IL-2, IL-6, IL-10, and serum beta2 microglobulin were 14.09 pg/ml, 42.92 pg/ml, 43.02 pg/ml, and 6.63 ug/L, respectively. Median levels were 7.23 pg/ml for IL-2, 44.74 pg/ml for IL-6, 31.11 pg/ml for IL-10, and 7.29 ug/L for serum beta2 microglobulin. IL-2 positively correlated with hemoglobin and platelet count but negatively correlated with lymphocyte count and serum LDH levels. Conversely, IL-6, IL-10 and Sß2M were positively correlated with lymphocyte count and serum LDH levels but negatively correlated with hemoglobin and platelet count. Comparison across Modified Rai and Binet staging revealed decreasing IL-2 levels (range 35.68pg/ml to 3.55mg/ml, p value 0.00001) and increasing IL-6 (15.05pg/ml to 58.95pg/ml, p value 0.03), IL-10 (2.11pg/ml to 76.11pg/ml, p value 0.00001), and Sß2M values (2.96ug/ml to 8.17ug/ml, p value 0.00001) with disease progression from Low to Intermediate and High risks groups. IL-6 and IL-10 has been found significant positively correlated (p value 0.00001) while IL-2 negatively correlated (p value 0.00001) with Sß2M levels Conclusion Our study found that blood levels of IL-6, IL-10, and Sß2M rose with CLL progression, as did Interleukin-2 in the early stages of the disease and should be evaluated as a novel clinical prognostic marker for predicting early disease load and an aggressive treatment regimen.","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"100 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145202933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"B-014 Analytical performance evaluation of the Abbott Vitamin assays on the Alinity ci system","authors":"Marvin Berman","doi":"10.1093/clinchem/hvaf086.412","DOIUrl":"https://doi.org/10.1093/clinchem/hvaf086.412","url":null,"abstract":"Background Vitamins can be crucial for diagnosing and managing health conditions related to low or excessive intake and for monitoring the effectiveness of dietary changes or supplement strategies. Abbott provides an extensive menu of vitamin assays which aid in the diagnosis and management of many health conditions such as deficiency or excess. Assays such as Vitamin D, Vitamin B12 and Vitamin C are used to monitor bone health, neurological function and immune system function respectively. Thus, vitamins are valuable for disease risk assessment. Homocysteine is an amino acid that plays a crucial role in cell metabolism and its levels are closely linked to vitamins B12 and folate (vit B9) deficiencies. Recent guideline changes to Vitamin D (Endo Society 2024) and B12 (Nice 2024) support the need for accurate assay performance. The Alinity ci system is part of a unified family of systems that are engineered for flexibility, efficiency, and decreased system down time. The design is based on insights from customers, resulting in a number of benefits including a smaller footprint, improved workflow, and great throughput with up to 200 tests per hour. The objective of this study is to demonstrate the analytical performance of representative assays from the Vitamin Panel of the Alinity i system, which consists of assays that utilize photometric technology for the quantitative determination of analytes in human serum or plasma. Methods Key performance testing including precision, limit of quantitation (LoQ), endogenous interferents, linearity and method comparison were assessed per Clinical and Laboratory Standards Institute (CLSI) protocols. Precision was assessed by testing controls and panels twice per day for 20 days on 2 instruments. Sensitivity was determined with 3 reagent lots on 2 instruments. Endogenous compounds were evaluated at a minimum of one analyte concentration. Linearity was assessed using a minimum of 6 panels that spanned the measuring interval. Method comparison was performed by measuring a minimum of 100 specimens on Alinity and the comparator method. The assay measuring interval was defined by the range for which acceptable performance for bias, imprecision, and linearity was met. Results The observed results for precision were 4.1 to 9%. Alinity method comparison vs ARCHITECT demonstrated slopes of 0.95 to 1.04 with correlation coefficients of 0.96 to 1.00. All assays demonstrated equivalent sensitivities, linearity, interferents and measuring intervals to ARCHITECT. Conclusion Standardization of the Abbott assays ensures the assays meet current guidelines. The vitamin panel of assays on the Abbott Alinity i platform demonstrated acceptable performance for precision, sensitivity, interferents and linearity. Method comparison data showed equivalency with the on-market assays, which verified the performance of these products on the Alinity i system.","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"19 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145203001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"B-185 Why chromatography still matters: the case of an interference in two benzodiazepines LC-MS/MS methods from hospital and reference laboratories","authors":"Marlen Menlyadiev, Mengyuan Ge, Raymond Suhandynata, Sheng-Ying Lo","doi":"10.1093/clinchem/hvaf086.578","DOIUrl":"https://doi.org/10.1093/clinchem/hvaf086.578","url":null,"abstract":"Background In clinical toxicology testing, interferences causing false-positive or negative results are usually associated with immunoassays used for drug screening. Liquid chromatography tandem mass spectrometry (LC-MS/MS) as toxicology’s gold-standard, on the other hand, is often praised for being free of such interferences. This is not always true in practice, however, especially when it comes to using short LC-MS/MS methods for analyzing complex specimens from patients on multiple medications. In this work we report on the observation of the inability of two independently developed LC-MS/MS benzodiazepines methods (from hospital and national reference laboratories) to quantify the metabolite of the CNS depressant clonazepam, 7-amoniclonazepam, due to an unknown interfering substance; and how the third method’s chromatographic performance was likely responsible for successful analyte quantification. Methods Random urine from a patient prescribed 0.5 mg oral clonazepam BID with the last dose of the medication taken 4 hours prior to specimen collection was obtained. The specimen was initially analyzed by Geisinger medical laboratory (GML) on a Sciex 5500 triple quadrupole mass spectrometer and later referred to Quest Diagnostics’ Nichols Institute (QD) and University of California San Diego’s clinical toxicology laboratory (UCSD) for reanalysis. The reporting cutoff levels for 7-aminoclonazepam for GML, QD and UCSD were, respectively, 20, 25 and 20 ng/mL. Additionally, the specimen was analyzed by high resolution MS at UCSD on a Waters Xevo G2 LC-QTOF-MS with the hope of identifying possible interfering substances by spectral library matching. Results At GML, the processed LC-MS/MS batch for the specimen was found acceptable. Two transitions (286.1/222 and 286.1/121) were monitored for quantification and qualification of 7-amoniclonazepam at 0.9 min. Upon inspection of the extracted ion chromatograms (XICs) for the specimen, a small secondary peak was observed for the 286.1/222 transition (∼5% of the base peak, chromatographically resolved) and larger (∼70% of base peak, incompletely resolved) for 286.1/121 transition. The quantifier/qualifier ion ratio (even with manual integration) was outside of the acceptability range of 7-aminoclonazepam indicating the presence of an interferent. Although reporting a “negative” result for this specimen was possible, reported recent clonazepam use by the patient and retention time match led to the request for specimen reanalysis at QD (“unable to report quantitative result due to drug/chemical interference”) and UCSD (concentration of 7-aminoclonazepam 111 ng/mL). Based on UCSD’s quantitative results, the patient’s compliance status was determined as compliant. Supplementary LC-QTOF-MS analysis at UCSD identified several analytes, including sertraline, levetiracetam and quetiapine (listed in the patient chart), providing a list of candidate interferents to subsequently evaluate in future studies. Conclusion ","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"39 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145203003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"B-127 Anti-CCP IgG Chemiluminescence Automatic Immunoassay for Rheumatoid Arthritis (RF) In-vitro Diagnostic on AutoLumo® 2000 Plus Platform","authors":"Don Zheng","doi":"10.1093/clinchem/hvaf086.524","DOIUrl":"https://doi.org/10.1093/clinchem/hvaf086.524","url":null,"abstract":"Background CCP (cyclic citrullinated peptide) is a group of cyclic short peptides containing citrulline with peptidyl-arginine deiminase modification on the arginine residues. Anti-CCP antibodies are critical serological markers for diagnosing rheumatoid arthritis (RA), recognized in the ACR/EULAR 2010 diagnostic guidelines due to their high specificity (0.95-0.99) compared to rheumatoid factor (RF). Anti-CCP IgG can emerge years before clinical RA symptoms, offering valuable predictive potential for RA diagnosis. Built on AutoLumo® 2000 Automatic Chemiluminescence Immunoassay Analyzer platform, here we introduce an anti-CCP In-vitro Diagnostics that delivers superior performance in accordance with requirements of clinical laboratories and hospitals. Methods This assay utilizes a two-step indirect method in which a diluted serum sample is combined with streptavidin-labeled microparticles and biotin-labeled CCP antigen, facilitating the binding of anti-CCP IgG antibodies to the antigen. After a washing step, an enzyme conjugate containing mouse anti-human IgG is added, promoting the formation of an immunological complex with the bound anti-CCP IgG on the solid phase. Finally, the addition of a chemiluminescent substrate triggers a reaction that is measured in relative light units (RLUs) intensities, that is proportional to the concentration of anti-CCP IgG antibodies in the serum. Analytical performance, stability, and method comparison with the Elecsys anti-CCP assay on Roche Cobas were assessed according to Clinical & Laboratory Standards Institute (CLSI) guideline Results The analytical performance evaluation of the Anti-CCP IgG CLIA Microparticles assay demonstrates its reliability in detecting IgG antibodies to CCP in human serum. The assay exhibits high analytical sensitivity, with a limit of blank (LOB) at 0.5 AU/mL, a limit of detection (LOD) at 2.0 AU/mL, and a limit of quantitation (LOQ) at 8.0 AU/mL, ensuring precise measurement. The trueness was evaluated, and the deviation of expected and measured results is within the ±10%. The assay showed excellent specificity, exhibiting no interference from common endogenous and exogenous substances. A high linearity with R=0.99 was observed within the measuring range of 8.0-500 AU/mL. Method comparison with the Elecsys anti-CCP IgG assay on Roche Cobas showed a 96.5% total coincidence rate across 200 clinical samples. Additionally, the AutoLumo® anti-CCP IgG assay demonstrated good stability, maintaining performance for up to 12 months when stored at 2–8°C based on real-time stability data. Conclusion Anti-CCP IgG CLIA microparticles assay performed on Autolumo® 2000 Plus system has demonstrated superior clinical performance with 96.5% total coincidence as compared to the Elecsys anti-CCP IgG assay on Roche Cobas. It also showed excellent analytical performance and high throughput capabilities. The AutoLumo® A2000 Plus has proven to be a robust and reliable platform for the autoimmunity anti","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"23 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145203004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"B-260 A Novel Bioluminescent, Multi-Epitope Assay to Detect Alzheimer’s Disease-Specific Tau Consistent with Alzheimer’s Amyloidosis","authors":"Josh Soldo, Melanie Dart, Khairul Ansari, Emily Torio, Val Ressler, Cassandra Brouette","doi":"10.1093/clinchem/hvaf086.647","DOIUrl":"https://doi.org/10.1093/clinchem/hvaf086.647","url":null,"abstract":"Background Early and accurate detection of amyloidosis and diagnosis of Alzheimer’s disease (AD) is crucial for effective management and treatment with new FDA-approved amyloid beta plaque-reducing therapeutics such as Lecanemab and Donanemab. Amyloid positron emission tomography (PET) imaging is the gold standard for detecting amyloid beta plaque in the brain but is expensive, requires radioactive tracers, and presents significant logistical challenges. Cerebrospinal fluid (CSF) biomarker testing is invasive and poses risks to patients. Recently, blood-based biomarkers, particularly phosphorylated Tau (pTau) assays, show promise in detecting amyloidosis and aiding AD diagnostics in patients with cognitive decline. However, existing pTau assays exhibit variability in sensitivity and specificity, leading to a diagnostic \"grey zone\" in 10–30% of tested patients. Given these limitations, there is a significant unmet need for a simple, non-invasive blood test that accurately detects amyloid pathology for early detection and disease progression monitoring. Here, we developed an ultra-sensitive blood test that detects Alzheimer’s disease-specific tau (AD Tau), enabling both early and late-stage amyloid beta plaque detection. Methods A novel multi-epitope assay was designed to capture, purify, and detect AD Tau. EDTA plasma from amyloid PET-confirmed individuals (amyloid beta plaque absent, n=23; amyloid beta plaque present, n=27) was pre-analytically conditioned and cleared of heterophilic and autoantibody interferences using clean beads. AD Tau was captured and purified using capture beads coated with multi-epitope targeting antibodies. Following biomarker capture, AD Tau peptides were eluted and neutralized into assay buffer containing non-ionic detergent to maintain peptide solubility. A ternary split-NanoLuc luciferase complementation reporter system was used as the detection module. This system used two small reporter peptides appended to AD Tau-specific antibody reagents and a polypeptide protein. Binding of the tagged antibodies to two different AD Tau-specific epitopes on purified AD Tau generates a stable bioluminescent signal through proximity-induced complementation between the reporter peptides and polypeptide protein in the presence of a luminogenic substrate. The AD Tau biomarker was detected using a luminescent plate reader. A calibrator was used to derive a ratio-metric value from the assay output, which facilitated simple yes/no results based on a predefined cutoff value of 1.000. Results Semi-quantitative analysis of 50 plasma samples showed that individuals with PET-confirmed amyloid beta plaque deposits had significantly higher AD Tau levels than those without (p < 0.0001). Categorizing the assay results into a binary ‘Yes/No’ outcome demonstrated an Overall Percent Agreement (OPA) of 88.0% and an Area Under the Receiver Operating Characteristic Curve (AUC-ROC) of 93.0%, indicating high reliability and accuracy compared to am","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"36 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145203156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A-327 Rapid Antifungal Susceptibility Testing System for Yeasts Based on Fast Cell Growth","authors":"Zeqi Zhou, Xiuzhen Wu, Yaonan Lin, Ying Wang, Yuan Zhang, He Wang, Yan Su, Shigui Liu","doi":"10.1093/clinchem/hvaf086.315","DOIUrl":"https://doi.org/10.1093/clinchem/hvaf086.315","url":null,"abstract":"Background Due to the growing burden of fungal infections and a recent rise in antifungal resistance, antifungal susceptibility testing (AFST) is of increasing importance. The common methods of AFST for yeasts have turnaround times of 24 to 48 h. Given the urgency of adequate antifungal treatment in invasive mycoses, rapid antifungal susceptibility testing is urgently needed in clinics to treat invasive fungal infections with the appropriate antifungal drugs and to slow the emergence of antifungal resistance. Methods Here, we demonstrate a rapid AFST by measuring the metabolism in fungal cells using resazurin and a medium that promotes the growth and metabolism of fungal cells (Fig). A total of 32 clinical fungal strains were randomly analyzed from the Peking Union Medical College Hospital. Species of these strains were commonly found in patients with systemic infections, including 9 Candida albicans, 5 Candida krusei, 3 Candida tropicalis, 3 Candida parapsilosis, 3 Candida lusitaniae, 7 Candida glabrata, and 2 Candida guilliermondii. The Sensititre YeastOne panel was performed according to the manufacturer*s instructions as reference methods. For the rapid AFST method, MICs were determined at 6 h of incubation. MICs for the YeastOne panel were read at 24 h of incubation. The overall agreement within +/- 2 dilutions by both methods was calculated against ten antifungal agents. Results Considering the Sensititre YeastOne Colorimetric Broth method as a comparator method, ten antifungal agents (?uconazole, itraconazole, voriconazole, posaconazole, isavuconazole, caspofungin, micafungin, anidulafungin, amphotericin B, and 5-flucytosine) showed an essential agreement of > 90%. Conclusion Therefore, this rapid AFST can be considered as an optional method that can obtain results and interpretations faster than previous methods. This method overcomes the limitation of slow growth in conventional methods and has the potential for the rapid diagnosis of candidemia and other clinical fungal infections.","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"19 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145203210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"B-143 Defining Proximity Limits for Semi-Annual Analytical Measurement Range Verification Studies","authors":"Anil Kiran Chokkalla, Jenn Rider, Eric Hanson, Kimberly Bennet, Carin Flom, Jody Thompson, Kristin Luckenbill, Christopher Koch","doi":"10.1093/clinchem/hvaf086.537","DOIUrl":"https://doi.org/10.1093/clinchem/hvaf086.537","url":null,"abstract":"Background Regulatory requirements by College of American Pathologists (CAP) require a semi-annual analytical measurement range (AMR) verification for analytes with less than 3-point calibrations. Proximity limits define the closeness of standards/linearity material to the lower limit of quantitation (LLoQ) and upper limit of quantitation (ULoQ) for a given analyte. These limits may be expressed in concentration units or percentages. Clinical Laboratory Standards Institute (CLSI) EP06-ED2 suggests method-specific proximity limits based on the analytical imprecision at the LLoQ and ULoQ. CAP recommends 10-15% at ULoQ and “reasonably close” to the LLoQ. Clearly, this requirement is subject to the Medical Director*s discretion. The aim of this study is to establish and standardize proximity limits based on workgroup consensus at a large rural health network. Methods A workgroup was formed to standardize the semi-annual AMR verification practices with key representatives from over 40 laboratories. Majority of the health system utilizes Abbott Alinity or Architect instruments for chemistry and immunoassay tests. Linearity material from third-party vendors like Maine Standards or AUDIT is used to assess the acceptability of established proximity limits. Analytical imprecision of the low level quality control material is taken into consideration for establishing low proximity limits. Results Proximity limits were established for 115 analytes spanning key testing areas such as chemistry, endocrinology, immunology, tumor markers and toxicology. Multiples of LLoQ or analytical imprecision at the lower end and 20% of the ULoQ at the upper end was reviewed for acceptability using linearity material. An exemplary proximity limit criteria for comprehensive metabolic panel is shown in Table 1. Importantly, these consensus based proximity limits considered crucial factors like analytical imprecision, clinical impact of error and the availability of test material near the limits. In addition to total allowable error, proximity limits could be utilized as acceptance criteria in the EP evaluator linearity and calibration verification module for semi-annual AMR verification studies. Conclusion Defining proximity limits in semi-annual AMR studies are crucial for evaluating the accuracy of quantitative measurement procedure and for regulatory compliance. Due to practical challenges, current regulations do not provide a formulary of proximity limits. Here we provide recommendations for method-specific proximity limits.","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"8 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145203314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A-223 Laboratory Process Tracker (LPT): a tool for real-time tracking of samples, instruments, and workflow steps used in clinical mass spectrometry testing","authors":"Difei Sun, Bruce Leimbrock, Makarand Ponneri, Michael Stiene, Dawn-Marie Murphy McLean, Rosemary Estalilla, Alex Stefou, Danijela Konforte","doi":"10.1093/clinchem/hvaf086.217","DOIUrl":"https://doi.org/10.1093/clinchem/hvaf086.217","url":null,"abstract":"Background Liquid chromatography-tandem mass spectrometry (LC-MS/MS) has seen ever increasing adoption by clinical laboratories. Most MS-based tests are laboratory-developed tests (LDTs). Common pre-analytical workflows include multiple method-specific steps such as sample aliquoting, extraction, dry-down, reconstitution and data acquisition on LC-MS/MS. Even when individual steps are automated, most laboratories find it challenging to track them to detect and correct errors in real-time. This remains a largely manual process. Here we describe features and benefits of the in-house developed software, Laboratory Process Tracker (LPT), which uses a system of barcodes to enable real-time tracking of LC-MS/MS batches throughout the sample preparation and data acquisition steps. Methods LPT is software developed using .NET 6 and Visual Studio Code. The LPT software settings were customized to reflect method-specific workflow and step-specific acceptance criteria. The following describes how it works for each method. 1. LPT generates 2D barcode labels that are assigned to each instrument and each trained user. 2. A new batch is created in LPT by scanning the user barcode, selecting the pre-programmed method name, uploading the batch specific sample list, and entering the batch number. The batch-specific barcodes are printed to label primary sample racks and 96-well plates for secondary samples. 3. The batch processing is then tracked step-by-step by scanning the barcodes of instruments, users, and rack/plate(s)/sample at the beginning of each step. LPT flags a step if the value entered fails to meet the passing criteria. The user can determine how to correct the error; it may require restarting the step, the whole batch, or even aborting the batch. 4. Finally, batches with addressed error flags are made available for manual review and sign-off after the batch is completed. Batches without errors are auto signed off by LPT. Results LPT was extensively validated and has been used in our laboratory for six LC-MS/MS methods since 2022. During this time, LPT has been used to successfully track more than 200 batches of samples per month. Less than 10% of all batches were flagged since they failed one or more acceptance criteria built into the software. The most common errors are due to batch mix-up, one step skipped or repeated, wrong instrument used, and processing time not matching the time allowance. Since its implementation, LPT has helped the lab achieve time and cost savings in error detection and mitigation. The additional benefits of LPT include a daily dashboard for tracking the status of all batches, summary of common operation errors, help with investigation and troubleshooting. Conclusion LPT software is an end-to-end pre-analytical workflow tracking tool. It is intuitive and user-friendly. In our clinical MS laboratory, it contributes to quality improvement, risk management and cost reduction. Collaboration among operations, clinical/scientific,","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"28 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145203318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"B-177 Selective and sensitive quantitation of 18 steroids in human serum using Thermo Scientific™ Stellar™ mass spectrometer","authors":"Jingshu Guo, Lauren Bishop, Courtney Patterson, Alan Atkins, Kerry Hassell","doi":"10.1093/clinchem/hvaf086.570","DOIUrl":"https://doi.org/10.1093/clinchem/hvaf086.570","url":null,"abstract":"Background Successful biomarker quantitation in complex matrices requires sensitivity and specificity to ensure the measured signal is attributed to the targeted analytes. To reduce background interferences and provide greater specificity, alternative fragmentation mechanisms and/or MS3 fragmentation are an efficient solution. The Thermo Scientific™ Stellar™ mass spectrometer (MS) is a hybrid quadrupole, dual-pressure linear ion trap MS that offers two types of orthogonal, yet complementary, collision-induced dissocation (CID) with rapid MS2 and MS3 scans. This poster is the first to demonstrate the advantages of utilizing multiple collision activations and MS3 scans provided by Stellar MS to the selective and sensitive quantification of 18 steroids in serum. Methods Commercially available 18 steroids standards, including 4 progestagens, 5 androgens, 2 estrogens, 3 mineralocorticoids, and 4 glucocorticoids, and their corresponding internal standards were serially diluted in 0.05% bovine serum albumin to generate calibrator samples over 4-orders of magnitude concentration range. Quality control human serum samples were purchased from Chromsystem. Steroids were extracted with protein precipitation, dried, and reconstituted in 50% methanol for the LCMS analysis. Multiple fragmentation schemes were evaluated and optimized on the Stellar MS, and the data was analyzed in Thermo Scientific™ TraceFinder™ software for the quantitative performance, including detection limit, quantitation limit and linearity. Results The detection of 18 steroids were optimized in Stellar MS under multiple fragmentation mechanisms (beam-type CID, resonance-type CID, and MS3 in different combinations) with polarity switching. Breakdown curves were generated to facilitate characteristic fragment ion selection to ensure high sensitivity and selectivity. Adaptive RT function was utilized to adjust the scheduled retention time window of the analyte in real-time to minimize any chromatographic changes such as aging column. Analytical performance of the calibration curves with R2 > 0.98 were achieved using a weighting factor of 1/x, and the limit of quantification (LOQ) values are established with % RSD < 20, ¦% Diff¦ < 20, with relative ion ratio meeting the values specified by EU Council Directive 96/23/EC. Comparing to the MS2 beam-type CID commonly used in contemporary triple quadruple MS, steroids such as cortisone, estradiol, and dihydrotestosterone benefited from the alternative, resonance-type CID and MS3 acquisition modes, resulting in a 2-10 fold increase of the LOQ values. Conclusion Stellar MS provides unique selectivity allied to fast acquisition for high-throughput and sensitive biomarker quantitation optimal for routine analysis","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"100 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145203117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A-030 Innovative Design and Evaluation of a BNP Assay with Enhanced Sample Stability","authors":"Yi Zhang","doi":"10.1093/clinchem/hvaf086.030","DOIUrl":"https://doi.org/10.1093/clinchem/hvaf086.030","url":null,"abstract":"Background Natriuretic peptides (NPs), including B-type NP (BNP) and N-terminal-proBNP (NT-proBNP), are widely used as cardiac function biomarkers, reflecting cardiac stretching. Both BNP and NT-proBNP measurements are globally accepted and used in clinical practice for the diagnosis of acute and chronic heart failure (HF), risk stratification, and monitoring therapeutic response. Although BNP and NT-proBNP have similar physiological values, they still differ in terms of clinical and laboratory applications. For example, BNP is less susceptible to renal function compared with NT-proBNP, yet it is highly unstable that can be rapidly digested, losing its immunologic activity in blood. Conventional sandwich BNP immunoassays use two antibodies targeting two different epitopes. Longer distances between epitopes increase the probability of proteolytic degradation. Therefore, specifically designing an antibody pair combination that targets the epitope without enzymatic degradation risk is highly valuable for laboratory practice. Methods The new BNP assay was designed based on the SES-BNPTM (Single Epitope Sandwich). Firstly, the stability of BNP molecules in both blood-based matrix and synthetic-based matrix was evaluated. Secondly, sample stability with different patient plasma samples was evaluated under different temperature conditions. Thirdly, a comprehensive evaluation of analytical performance of this new BNP assay was conducted, including the sensitivity (LoB, LoD, LoQ), specificity, precision, etc. Results Different forms of BNP molecules could stay stable under room temperature within eight hours or under 2-8? within 24 hours. Compared with commercial BNP assays, sample stability for plasma samples from different patients increased from four to eight hours under room temperature and from 12 to 24 hours under 2-8C. Furthermore, the new BNP assay demonstrated excellent analytical sensitivity, where the LOB, LOD, LOQ are 1.00, 2.00, 3.00 pg/mL, respectively. Total imprecision near the threshold of non-CHF population (100 ng/L) was < 5%. No cross-reactivity or interference from endogenous interferents was observed. Conclusion By combining with SES-BNPTM, a new BNP assay was developed to improve sample stability during storage. Stability of BNP molecules in both plasma matrix and in synthetic buffer matrix increased, and would be more convenient during laboratory practice. Through a comprehensive evaluation, this new BNP assay was demonstrated to be highly sensitive, specific and with high precision.","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"72 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145203154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}