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1.
Proc Natl Acad Sci U S A ; 121(33): e2407357121, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39110724

RESUMO

Satellite-based land use monitoring and farm-level traceability offer opportunities for targeted zero-deforestation interventions on private lands. Brazil's Rural Environmental Registry (Cadastro Ambiental Rural, or "CAR"), a land cadaster based on self-declaration of property boundaries, was created to monitor compliance with national forest laws. It has become an important enabling measure for sustainable supply chain initiatives like the Amazon Soy Moratorium. However, CAR enrollment is increasingly used to bolster illegal land claims, putting it at the heart of land grabbing dynamics. Self-declaration of properties in the CAR offers a unique situation to study land conflicts and their impact on land use decisions on a large scale. We quantified competing land claims among 846,420 registrations in the Brazilian Legal Amazon and applied a series of generalized linear mixed-effects models. We determined that CAR overlaps are more prevalent on larger registrations, in more densely settled areas, and in areas with less secure land tenure. We tested how landholders respond to land conflicts, finding significantly more deforestation and declared legal forest reserve on lands with multiple claims. CAR overlap results in an overestimation of forest reserves by up to 9.7 million hectares when considering double-counted and deforested areas of reserves, highlighting an overlooked form of Forest Code noncompliance. While the CAR continues to be used as evidence of land tenure, we conclude that the formalization of land claims through self-declarations is inadequate to decrease conflicts. CAR overlap information provides objective evidence of land conflict that authorities can leverage with field inspection to ensure peaceful occupation before issuing land titles.


Assuntos
Conservação dos Recursos Naturais , Brasil , Florestas , Humanos , Agricultura , Sistema de Registros , População Rural , Monitoramento Ambiental/métodos
2.
BMC Biol ; 22(1): 202, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39256748

RESUMO

BACKGROUND: Seafood is increasingly traded worldwide, but its supply chain is particularly prone to frauds. To increase consumer confidence, prevent illegal trade, and provide independent validation for eco-labelling, accurate tools for seafood traceability are needed. Here we show that the use of microbiome profiling (MP) coupled with machine learning (ML) allows precise tracing the origin of Manila clams harvested in areas separated by small geographic distances. The study was designed to represent a real-world scenario. Clams were collected in different seasons across the most important production area in Europe (lagoons along the northern Adriatic coast) to cover the known seasonal variation in microbiome composition for the species. DNA extracted from samples underwent the same depuration process as commercial products (i.e. at least 12 h in open flow systems). RESULTS: Machine learning-based analysis of microbiome profiles was carried out using two completely independent sets of data (collected at the same locations but in different years), one for training the algorithm, and the other for testing its accuracy and assessing the temporal stability signal. Briefly, gills (GI) and digestive gland (DG) of clams were collected in summer and winter over two different years (i.e. from 2018 to 2020) in one banned area and four farming sites. 16S DNA metabarcoding was performed on clam tissues and the obtained amplicon sequence variants (ASVs) table was used as input for ML MP. The best-predicting performances were obtained using the combined information of GI and DG (consensus analysis), showing a Cohen K-score > 0.95 when the target was the classification of samples collected from the banned area and those harvested at farming sites. Classification of the four different farming areas showed slightly lower accuracy with a 0.76 score. CONCLUSIONS: We show here that MP coupled with ML is an effective tool to trace the origin of shellfish products. The tool is extremely robust against seasonal and inter-annual variability, as well as product depuration, and is ready for implementation in routine assessment to prevent the trade of illegally harvested or mislabeled shellfish.


Assuntos
Bivalves , Aprendizado de Máquina , Microbiota , Alimentos Marinhos , Alimentos Marinhos/microbiologia , Animais , Bivalves/microbiologia , Comércio
3.
Mass Spectrom Rev ; 42(5): 1772-1807, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35532212

RESUMO

Food authentication and origin traceability are popular research topics, especially as concerns about food quality continue to increase. Mass spectrometry (MS) plays an indispensable role in food authentication and origin traceability. In this review, the applications of MS in food authentication and origin traceability by analyzing the main components and chemical fingerprints or profiles are summarized. In addition, the characteristic markers for food authentication are also reviewed, and the advantages and disadvantages of MS-based techniques for food authentication, as well as the current trends and challenges, are discussed. The fingerprinting and profiling methods, in combination with multivariate statistical analysis, are more suitable for the authentication of high-value foods, while characteristic marker-based methods are more suitable for adulteration detection. Several new techniques have been introduced to the field, such as proton transfer reaction mass spectrometry, ambient ionization mass spectrometry (AIMS), and ion mobility mass spectrometry, for the determination of food adulteration due to their fast and convenient analysis. As an important trend, the miniaturization of MS offers advantages, such as small and portable instrumentation and fast and nondestructive analysis. Moreover, many applications in food authentication are using AIMS, which can help food authentication in food inspection/field analysis. This review provides a reference and guide for food authentication and traceability based on MS.

4.
Crit Rev Food Sci Nutr ; : 1-14, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39257291

RESUMO

Process design strategies are important to prevent or reduce food safety risks in production systems. In this sense, the Codex Alimentarius presents a set of principles for good hygiene practices to guide food producers. However, studies in food safety often focus on analyzing and controlling implemented production processes without a policy of designing them with a preventive logic, leading to resource misallocation and noncompliance. This study aims to gather and analyze techniques, drivers, challenges, and research opportunities for food safety-driven process design. A systematic literature review was carried out following three steps: (i) Data collection, including 52 studies; (ii) Bibliometric analysis; and (iii) Content analysis, identifying techniques, drivers, challenges, and research opportunities. Three main themes in the subject were identified: process assessment models, risk assessment, and whole-chain traceability. Eleven design techniques were identified and compared according to their typology, structure, and coverage of themes addressed by the Codex Alimentarius. There is a gap in techniques addressing employee competence and personal hygiene. We suggest developing a tool encompassing the Codex Alimentarius good hygiene practices themes in process design to guide food safety-driven process development.

5.
Environ Sci Technol ; 58(41): 18335-18344, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39251361

RESUMO

The aging process of microplastics (MPs) affects their surface physicochemical properties, thereby influencing their behaviors in releasing harmful chemicals, adsorption of organic contaminants, sinking, and more. Understanding the aging process is crucial for evaluating MPs' environmental behaviors and risks, but tracing the aging process remains challenging. Here, we propose a multimodal deep learning model to trace typical aging factors of aged MPs based on MPs' physicochemical characteristics. A total of 1353 surface morphology images and 1353 Fourier transform infrared spectroscopy spectra were achieved from 130 aged MPs undergoing different aging processes, demonstrating that physicochemical properties of aged MPs vary from aging processes. The multimodal deep learning model achieved an accuracy of 93% in predicting the major aging factors of aged MPs. The multimodal deep learning model improves the model's accuracy by approximately 5-20% and reduces prediction bias compared to the single-modal model. In practice, the established model was performed to predict the major aging factors of naturally aged MPs collected from typical environment matrices. The prediction results aligned with the aging conditions of specific environments, as reported in previous studies. Our findings provide new insights into tracing and understanding the plastic aging process, contributing more accurately to the environmental risk assessment of aged MPs.


Assuntos
Aprendizado Profundo , Microplásticos , Monitoramento Ambiental/métodos , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Clin Chem Lab Med ; 62(2): 249-252, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-37698363

RESUMO

Alanine aminotransferase (ALT) represents the first-level test to detect individuals with hepatocellular damage of any etiology. However, it has been highlighted that the lack of assay harmonization may lead to overdiagnosis and unnecessary further testing if guideline-recommended fixed cut-offs are uncritically employed. To solve the issue of ALT (dis)harmonization and improve the interpretation of its values, a series of urgent actions for documenting and validating metrological traceability of serum ALT measurements, as described in this paper, are no longer postponeable. It is time that all medical laboratory stakeholders (in vitro diagnostic manufacturers, laboratorians, external quality assessment scheme organizers) actively co-operate to implement the ALT standardization in a concerted action following well-established theoretical assumptions and applying experimental approaches described in literature.


Assuntos
Técnicas de Laboratório Clínico , Gastroenterologia , Humanos , Alanina Transaminase , Padrões de Referência
7.
Clin Chem Lab Med ; 62(2): 280-287, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-37614121

RESUMO

OBJECTIVES: Recently, Abbott Diagnostics marketed a new generation of Alinity enzyme assays, introducing a multiparametric calibrator [Consolidated Chemistry Calibrator (ConCC)] in place of or in addition to factor-based calibrations. For alkaline phosphatase (ALP), both calibration options are offered, i.e., with ConCC (ALP2) and with an experimental calibration factor (ALP2F). Both options are declared traceable to the 2011 IFCC reference measurement procedure (RMP). Before to replace the old generation (ALP1) with the new one, we decided to validate the trueness of ALP2/ALP2F. METHODS: Three approaches were employed: (a) preliminary comparison on 48 native frozen serum samples with ALP1, of which traceability to RMP was previously successfully verified; (b) examination of three banked serum pools (BSP) with values assigned by RMP; (c) direct comparison with RMP on a set of 24 fresh serum samples. Bias estimation and regression studies were performed, and the standard measurement uncertainty associated with ALP measurements on clinical samples (uresult) was estimated and compared with established analytical performance specifications (APS). ConCC commutability was also assessed. RESULTS: A positive proportional bias was found with both ALP2 and ALP2F when compared to ALP1 and RMP. This positive bias was confirmed on BSP: in average, +13.1 % for ALP2 and +10.0 % for ALP2F, respectively. uresult were 13.28 % for ALP2 and 10.04 % for ALP2F, both not fulfilling the minimum APS of 4.0 %. Furthermore, ConCC was not commutable with clinical samples. CONCLUSIONS: Our results unearth problems in the correct implementation of traceability of Alinity ALP2/ALP2F, with the risk for the new assay to be unfit for clinical purposes.


Assuntos
Fosfatase Alcalina , Ensaios Enzimáticos Clínicos , Humanos , Soro , Calibragem , Padrões de Referência
8.
Clin Chem Lab Med ; 62(8): 1497-1504, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-38311825

RESUMO

In addition to the correct implementation of calibration traceability, the definition and fulfillment of maximum allowable measurement uncertainty (MAU) are essential in assuring that laboratory measurements are clinically usable. Across the entire calibration hierarchy, three major contributors to the measurement uncertainty (MU) budget are identified, starting with the higher-order reference providers, extending through the in vitro diagnostic (IVD) manufacturers and their processes for assigning calibrator values, and ending with medical laboratories generating the random variability of results reported to clinicians. To understand if it is possible to achieve MAU and, consequently, to fix the possible drawbacks, the definition of combined MU budget limits across the entire calibration hierarchy has a central role. In particular, quality specifications for MU of reference and commercial calibrator materials should be defined according to the MAU on clinical samples. All involved stakeholders (i.e., higher-order reference providers, IVD manufacturers, medical laboratories) should be prepared to improve their performance whenever the clinical application of the test is made questionable by the failure to achieve MAU.


Assuntos
Controle de Qualidade , Incerteza , Calibragem , Humanos , Padrões de Referência , Técnicas de Laboratório Clínico/normas , Técnicas de Laboratório Clínico/economia , Orçamentos
9.
Clin Chem Lab Med ; 62(8): 1490-1496, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-38353168

RESUMO

To be accurate and equivalent among assays, laboratory results should be traceable to higher-order references and their quality should fulfill maximum allowable measurement uncertainty (MU) as defined to fit the intended clinical use. Accordingly, laboratory professionals should estimate and validate MU of performed tests using appropriate analytical performance specifications (APS). Current consensus supports the derivation of APS by using one of the three models established by the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) Strategic Conference held in Milan in 2014. It is recognized that some models are better suited for certain measurands than for others and the attention should be primarily directed towards their biological and clinical characteristics. Among others, model 3 should reflect the state of the art of the measurements that can be defined as the best analytical performance that is technically achievable. Taking serum C-reactive protein and ferritin as examples, here we describe the theoretical premises and the experimental protocol to be used to derive APS for MU when a measurand is allocated to this model. Although the model lacks a direct relationship with clinical outcomes, useful information about the in vitro diagnostic medical device performance and the average quality of provided results may be obtained.


Assuntos
Ferritinas , Humanos , Ferritinas/sangue , Ferritinas/análise , Proteína C-Reativa/análise , Proteína C-Reativa/normas , Incerteza , Modelos Teóricos , Técnicas de Laboratório Clínico/normas
10.
Clin Chem Lab Med ; 62(8): 1462-1469, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-38579121

RESUMO

The goal of metrological traceability is to have equivalent results for a measurand in clinical samples (CSs) irrespective of the in-vitro diagnostic medical device (IVD-MD) used for measurements. The International Standards Organization standard 17511 defines requirements for establishing metrological traceability of values assigned to calibrators, trueness control materials and human samples used with IVD-MDs. Each step in metrological traceability has an uncertainty associated with the value assigned to a material. The uncertainty at each step adds to the uncertainty from preceding steps such that the combined uncertainty gets larger at each step. The combined uncertainty for a CS result must fulfil an analytical performance specification (APS) for the maximum allowable uncertainty (umax CS). The umax CS can be partitioned among the steps in a metrological traceability calibration hierarachy to derive the APS for maximum allowable uncertainty at each step. Similarly, the criterion for maximum acceptable noncommutability bias can be derived from the umax CS. One of the challenges in determining if umax CS is fulfilled is determining the repeatability uncertainty (u Rw) from operating an IVD-MD within a clinical laboratory. Most of the current recommendations for estimating u Rw from internal quality control data do not use a sufficiently representative time interval to capture all relevant sources of variability in measurement results. Consequently, underestimation of u Rw is common and may compromise assessment of how well current IVD-MDs and their supporting calibration hierarchies meet the needs of clinical care providers.


Assuntos
Padrões de Referência , Humanos , Calibragem , Incerteza , Guias como Assunto , Laboratórios Clínicos/normas , Técnicas de Laboratório Clínico/normas , Controle de Qualidade
11.
Clin Chem Lab Med ; 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38687497

RESUMO

Non-harmonization of laboratory results represents a concrete risk for patient safety. To avoid harms, it is agreed that measurements by in vitro diagnostic medical devices (IVD-MD) on clinical samples should be traceable to higher-order references and adjusted to give the same result. However, metrological traceability is not a formal claim and has to be correctly implemented, which in practice does not happen for a non-negligible number of measurands. Stakeholders, such as higher-order reference providers, IVD manufacturers, and External Quality Assessment organizers, have major responsibilities and should improve their contribution by unambiguously and rigorously applying what is described in the International Organization for Standardization 17511:2020 standard and other documents provided by the international scientific bodies, such as Joint Committee on Traceability in Laboratory Medicine and IFCC. For their part, laboratory professionals should take responsibility to abandon non-selective methods and move to IVD-MDs displaying proper selectivity, which is one of the indispensable prerequisites for the correct implementation of metrological traceability. The practicality of metrological traceability concepts is not impossible but relevant education and appropriate training of all involved stakeholders are essential to obtain the expected benefits in terms of standardization.

12.
Clin Chem Lab Med ; 62(1): 77-84, 2024 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-37470304

RESUMO

OBJECTIVES: We report the results of glucose measurements performed during one year by the same measurement procedures (MPs) in 58 Norwegian hospital laboratories using control materials provided by external quality assessment (EQA) schemes from two different providers. The providers used materials with presumed vs. verified commutability and transfers of values using reference material vs. using a highest-order reference MP. METHODS: Data from six Labquality and three Noklus glucose EQA surveys were aggregated for each MP (Abbott Alinity, Abbott Architect, Roche Cobas, and Siemens Advia) in each scheme. For each EQA result, percent difference from target value (% bias) was calculated. Median percent bias for each MP per scheme was then calculated. RESULTS: The median % biases observed for each MP in the Labquality scheme were significantly larger than those in the Noklus scheme, which uses verified commutable control materials and highest-order reference MP target values. The difference ranged from 1.2 (Roche Cobas, 2.9 vs. 1.7 %) to 4.4 percentage points (Siemens Advia, 3.2 % vs. -1.2 %). The order of bias size for the various MPs was different in the two schemes. In contrast to the Labquality scheme, the median % biases observed in the Noklus scheme for Abbott Alinity (-0.1 %), Abbott Architect (-0.5 %), and Siemens Advia (-1.2 %) were not significantly different from target value (p>0.756). CONCLUSIONS: This study underlines the importance of using verified commutable EQA materials and target values traceable to reference MPs in EQA schemes designed for assessment of metrological traceability of laboratory results.


Assuntos
Laboratórios Hospitalares , Laboratórios , Humanos , Controle de Qualidade , Glucose , Viés , Valores de Referência , Padrões de Referência
13.
Clin Chem Lab Med ; 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39311541

RESUMO

OBJECTIVES: Until now, the external quality assessment (EQA) of glucose point-of-care testing (POCT) has lacked a high quality, suitable and commutable control material to assess measurement accuracy. Here we present a concept for determining the accuracy of glucose measurements, which uses human whole blood and does not require stabilising agents. METHODS: This new generation of quality control samples uses a bead that contains a specific amount of glucose. The bead is then dissolved in a whole blood matrix by the EQA participant immediately before the POCT. We analysed its suitability as an EQA material with respect to its reproducibility, homogeneity and stability, and applied it in an EQA pilot study. The glucose target value was determined using the reference measurement procedure and served as an evaluation criterion for the accuracy of the EQA survey results. RESULTS: The homogeneity and stability of the new control material fulfilled the quality requirements of ISO 17043. Based on the reference measurement value for glucose, the results of the pilot EQA scheme showed a pass rate of 84.6 % for the participating POCT devices. The acceptance limit was a 15 % permitted deviation from the target value according to Rili-BAEK. All of the device collectives deviated from the target value by 0-4.4 % with the exception of one device type, which deviated by 21 %. CONCLUSIONS: The new concept offers, for the first-time, whole blood-based trueness controls for glucose POCT analysis for external quality assurance. The concept does not require the addition of any stabilising reagent and is easy to use.

14.
Clin Chem Lab Med ; 62(7): 1327-1338, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38549258

RESUMO

OBJECTIVES: Primidone is an anticonvulsive drug used in the treatment of epilepsy and essential tremor. It offers beneficial effects in controlling seizures, but its usage is also associated with possible side effects. To ensure optimal therapy, it is crucial to measure its concentration through accurate quantification methods. Therefore, our main goal was to develop and validate a new reference measurement procedure (RMP) for accurately measuring primidone levels in human serum and plasma. METHODS: In our study, we focused on the separation of primidone from both known and unknown interferences using a C18 column. To achieve accurate sample preparation, we developed a protocol involving protein precipitation followed by a high dilution step. The validation of the assay and determination of measurement uncertainty were carried out following guidelines from organizations such as the Clinical and Laboratory Standards Institute, the International Conference on Harmonization, and the Guide to the Expression of Uncertainty in Measurement. These rigorous validation processes ensure the reliability and accuracy of our method for quantifying primidone levels in human serum and plasma samples. RESULTS: The RMP was shown to be highly selective and specific, with no evidence of matrix interference. It can be used to quantify primidone in the range of 0.150-30.0 µg/mL. Intermediate precision was less than 4.0 %, and repeatability CV ranged from 1.0 to 3.3 % across all concentration levels. The relative mean bias ranged from 0.1 to 3.9 % for native serum levels, and from -2.6 to 2.8 % for lithium-heparin plasma levels. The measurement uncertainties for single measurements and target value assignment were 1.5-4.1 % and 0.9-1.0 %, respectively. CONCLUSIONS: In this study, we introduce an innovative LC-MS/MS-based candidate RMP specifically designed for primidone in human serum and plasma. Our RMP offers a traceable platform, facilitating the standardization of routine assays and enabling the evaluation of clinically relevant samples. With this novel approach, we aim to enhance the accuracy and reliability of primidone measurements, ultimately benefiting the field of clinical research and patient care.


Assuntos
Primidona , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Espectrometria de Massas em Tandem/normas , Primidona/sangue , Cromatografia Líquida/métodos , Cromatografia Líquida/normas , Padrões de Referência , Reprodutibilidade dos Testes , Técnicas de Diluição do Indicador , Limite de Detecção , Anticonvulsivantes/sangue , Espectrometria de Massa com Cromatografia Líquida
15.
Clin Chem Lab Med ; 62(7): 1314-1326, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38407268

RESUMO

OBJECTIVES: Phenobarbital serves as an antiepileptic drug (AED) and finds application in the treatment of epilepsy either as monotherapy or adjunctive therapy. This drug exhibits various pharmacodynamic properties that account for its beneficial effects as well as potential side effects. Accurate measurement of its concentration is critical for optimizing AED therapy through appropriate dose adjustments. Therefore, our objective was to develop and validate a new reference measurement procedure (RMP) for the accurate quantification of phenobarbital levels in human serum and plasma. METHODS: A sample preparation protocol based on protein precipitation followed by a high dilution step was established in combination with a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method using a C8 column to separate target analytes from known and unknown interferences. Assay validation and determination of measurement uncertainty were performed based on current guidelines. Selectivity and Specificity were assessed using spiked serum and plasma samples; to investigate possible matrix effects (MEs) a post-column infusion experiment and a comparison of standard line slopes was performed. Precision and accuracy were determined within a multiday precision experiment. RESULTS: The RMP was shown to be highly selective and specific, with no evidence of matrix interferences. It can be used to quantify phenobarbital in the range of 1.92 to 72.0 µg/mL. Intermediate precision was less than 3.2 %, and repeatability coefficient of variation (CV) ranged from 1.3 to 2.0 % across all concentration levels. The relative mean bias ranged from -3.0 to -0.7 % for native serum levels, and from -2.8 to 0.8 % for Li-heparin plasma levels. The measurement uncertainties (k=1) for single measurements and target value assignment were 1.9 to 3.3 % and 0.9 to 1.6 %, respectively. CONCLUSIONS: A novel LC-MS/MS-based candidate RMP for the quantification of phenobarbital in human serum and plasma is presented which can be used for the standardization of routine assays and the evaluation of clinically relevant samples.


Assuntos
Fenobarbital , Espectrometria de Massas em Tandem , Humanos , Fenobarbital/sangue , Espectrometria de Massas em Tandem/métodos , Espectrometria de Massas em Tandem/normas , Cromatografia Líquida/métodos , Cromatografia Líquida/normas , Anticonvulsivantes/sangue , Padrões de Referência , Análise Química do Sangue/métodos , Análise Química do Sangue/normas , Técnicas de Diluição do Indicador , Espectrometria de Massa com Cromatografia Líquida
16.
Clin Chem Lab Med ; 62(7): 1339-1351, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38515344

RESUMO

OBJECTIVES: A reference measurement procedure (RMP) using isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) was developed and validated with the aim of accurately measuring carbamazepine-10,11-epoxide concentrations in human serum and plasma. METHODS: To establish traceability to SI units, the absolute content of the reference material was determined using quantitative nuclear magnetic resonance (qNMR) spectroscopy. As sample preparation a protein precipitation protocol followed by a high dilution step was established. Chromatographic separation from carbamazepine and potential metabolites was achieved using a C18 stationary phase. Selectivity, specificity, matrix effects, precision and accuracy, inter-laboratory equivalence, and uncertainty of measurement were evaluated based on guidelines from the Clinical and Laboratory Standards Institute, the International Conference on Harmonization, and the Guide to the Expression of Uncertainty in Measurement. RESULTS: The RMP demonstrated very good selectivity and specificity, showing no evidence of a matrix effect. This enabled accurate quantification of carbamazepine-epoxide in the concentration range of 0.0400-12.0 µg/mL. The intermediate precision was found to be less than 2.1 %, and the repeatability coefficient of variation (CV) ranged from 1.2 to 1.8 % across all concentration levels. Regarding accuracy, the relative mean bias varied from 1.4 to 2.5 % for native serum levels and from 1.4 to 3.5 % for Li-heparin plasma levels. The measurement uncertainty for single measurements ranged from 1.6 to 2.1 %. CONCLUSIONS: In this study, we introduce a new LC-MS/MS-based candidate RMP for accurately measuring carbamazepine-10,11-epoxide in human serum and plasma. This novel method offers a traceable and dependable platform, making it suitable for standardizing routine assays and assessing clinically relevant samples.


Assuntos
Carbamazepina , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Espectrometria de Massas em Tandem/normas , Carbamazepina/sangue , Carbamazepina/análogos & derivados , Cromatografia Líquida/métodos , Cromatografia Líquida/normas , Padrões de Referência , Técnicas de Diluição do Indicador , Espectrometria de Massa com Cromatografia Líquida
17.
Clin Chem Lab Med ; 62(7): 1288-1300, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38105272

RESUMO

OBJECTIVES: To describe and validate an isotope dilution-liquid chromatograph-tandem mass spectrometry (ID-LC-MS/MS) based reference measurement procedure (RMP) for zonisamide to accurately measure serum and plasma concentrations. METHODS: Quantitative nuclear magnetic resonance (qNMR) spectroscopy was employed to determine the absolute content of the reference material used in order to establish traceability to SI units. Separation of zonisamide from known or unknown interferences was performed on a C8 column. For sample preparation a protocol based on protein precipitation in combination with a high dilution step was established. Assay validation and determination of measurement uncertainty were performed based on guidelines from the Clinical and Laboratory Standards Institute, the International Conference on Harmonization, and the Guide to the expression of uncertainty in measurement. RESULTS: The RMP was proven to be highly selective and specific with no evidence of a matrix effect, allowing for quantification of zonisamide within the range of 1.50-60.0 µg/mL. Intermediate precision was <1.4 % and repeatability CV ranged from 0.7 to 1.2 % over all concentration levels. The relative mean bias ranged from 0.0 to 0.8 % for native serum levels and from 0.2 to 2.0 % for Li-heparin plasma levels. The measurement uncertainties for single measurements and target value assignment ranged from 1.1 to 1.4 % and 0.8-1.0 %, respectively. CONCLUSIONS: We present a novel LC-MS/MS-based candidate RMP for zonisamide in human serum and plasma which provides a traceable and reliable platform for the standardization of routine assays and evaluation of clinically relevant samples.


Assuntos
Isoxazóis , Espectrometria de Massas em Tandem , Zonisamida , Humanos , Espectrometria de Massas em Tandem/métodos , Espectrometria de Massas em Tandem/normas , Zonisamida/sangue , Cromatografia Líquida/métodos , Cromatografia Líquida/normas , Isoxazóis/sangue , Padrões de Referência , Técnicas de Diluição do Indicador , Análise Química do Sangue/métodos , Análise Química do Sangue/normas , Espectrometria de Massa com Cromatografia Líquida
18.
Anal Bioanal Chem ; 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39297935

RESUMO

It is of significant importance to public health that reliable monitoring of nitroimidazoles be conducted, while certified reference materials (CRMs) are essential for accurate and reliable detection. A project has been initiated with the objective of developing nitroimidazole purity CRMs to ensure that results from nationwide monitoring laboratories for nitroimidazoles in antibiotic residues can be compared and traced. The candidates were successively characterized in terms of their structure by means of infrared (IR) spectroscopy and mass spectrometry (MS). The mass balance (MB) method and the quantitative nuclear magnetic resonance (qNMR) method were utilized to determine the purity of nitroimidazoles with remarkable accuracy. Furthermore, a methodical investigation was conducted on homogeneity, stability, and uncertainty. Six nitroimidazole purity CRMs, including tinidazole (GBW09252), secnidazole (GBW09286), ronidazole (GBW09288), metronidazole (GBW(E)090755), dimetridazole (GBW(E)090819), and ornidazole (GBW(E)090820), were finally manufactured following authorization from China's State Administration for Market Regulation (SAMR). By using these CRMs, it is possible to improve the traceability, accuracy, and comparability of nitroimidazole measurements in a range of agricultural products, protecting public health.

19.
Anal Bioanal Chem ; 416(16): 3645-3663, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38507042

RESUMO

Metrology is the science of measurement and its applications, whereas biometrology is the science of biological measurement and its applications. Biometrology aims to achieve accuracy and consistency of biological measurements by focusing on the development of metrological traceability, biological reference measurement procedures, and reference materials. Irreproducibility of biological and multi-omics research results from different laboratories, platforms, and analysis methods is hampering the translation of research into clinical uses and can often be attributed to the lack of biologists' attention to the general principles of metrology. In this paper, the progresses of biometrology including metrology on nucleic acid, protein, and cell measurements and its impacts on the improvement of reliability and comparability in biological research are reviewed. Challenges in obtaining more reliable biological and multi-omics measurements due to the lack of primary reference measurement procedures and new standards for biological reference materials faced by biometrology are discussed. In the future, in addition to establishing reliable reference measurement procedures, developing reference materials from single or multiple parameters to multi-omics scale should be emphasized. Thinking in way of biometrology is warranted for facilitating the translation of high-throughput omics research into clinical practices.


Assuntos
Proteômica , Humanos , Reprodutibilidade dos Testes , Proteômica/métodos , Padrões de Referência , Animais , Genômica/métodos , Multiômica
20.
Environ Res ; : 120026, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39299449

RESUMO

In this paper, a novel numerical model capable of high-resolution, accurate simulation of the accumulation, wash-off, and migration of nonpoint source (NPS) pollutants on roads is proposed, effectively addressing the challenge of limited pipe network data for high-density urban building communities. This approach is based on a 1D-2D hydrodynamic and water quality dynamic bidirectional coupling model: GAST-SWMM. The calculation accuracy of the GAST two-dimensional road NPS wash-off model is validated via comparison with experimental data. The obtained Nash-Sutcliffe efficiency (NSE) is greater than 0.8. Moreover, the model was used to simulate the NPSs in a densely populated urban region of Xi'an, China, lacking building community pipeline data. The NPS pollutant transport and fate under the influence of both road runoff and the building community hydrodynamic water quality during rainfall events with a specific return period were examined. The proposed model can effectively and accurately replicate the accumulation and removal of NPS pollutants on a two-dimensional road and their dynamic interaction with the drainage network. With increasing rainfall return period, the peak time of the surface contaminant total load is postponed. The maximum surface pollutant load durations during rainfall events with 2-, 10-, and 50-year return periods are 60, 75, and 80 minutes, respectively. During the peak surface pollutant load time, the overflow pollutant fraction can exceed 85% for a 50-year rainfall return period. The simulation method presented in this paper accurately captures the spatial and temporal variations in NPS pollutants in densely populated urban areas, even when pipe network data for building communities are lacking. This method offers valuable technical assistance for urban environmental management and water quality protection.

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