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1.
Food Chem ; 447: 139010, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-38513487

RESUMEN

Assessment of trace metal concentrations in plant oils has been considered a crucial quality control marker for potential health risks, oil flavour, and oxidative stability. A straightforward inductively coupled plasma mass spectrometry (ICP-MS) methodology was developed and validated through introduction of argon:oxygen gas mixture into plasma, allowing for a direct elemental analysis of organic matrices. This approach offers the advantage of a simple one-step preparation of plant oil samples with negligible contamination risks. The complete solubilization of the oil matrix enables the determination of total metal content from a single test tube with low dilution factor of 5. The modified plasma conditions resulted in the development of a robust and accurate ICP-MS method providing limits of detection at sub ng·g-1 levels. The ICP-MS method allowed the determination of trace levels of Ba, Cd, Cu, Fe, Mn, Pb, Sn, V, and Zn in olive, sunflower and rapeseed oils.


Asunto(s)
Oxígeno , Oligoelementos , Oxígeno/análisis , Oligoelementos/análisis , Metales , Aceites de Plantas/química , Espectrometría de Masas/métodos
2.
Artículo en Inglés | MEDLINE | ID: mdl-34492509

RESUMEN

Analytical methods used for quality control of plants and plant extracts are based on the identification and quantification of chemical markers to manage batch reproducibility and efficacy. The aim of this work was to assess the performance of a High Performance Thin Layer Chromatography (HPTLC) method developed for quality control of industrial dry extracts of ribwort plantain (P. lanceolata L.), using 2,2-diphenyl 1-picrylhydrazyle (DPPH) effect directed chemical reaction for antioxidant activity of acteoside, a phenylethanoid glycoside commonly used as a marker for P. lanceolata L., and to demonstrate the applicability of the Life Cycle Management of Analytical Methods concept to quantitative HPTLC-DPPH methods. The first step was the determination of the Analytical Target Profile (ATP) and Target Measurement Uncertainty (TMU), taking into account the quality control requirements for such extracts and the detection method applicable range. Once the desired range was established, an evaluation of the calibration function was conducted using several calibration models. Due to the lack of reference samples, spiked samples were used to evaluate the accuracy of the method by means of Total Analytical Error (TAE) determination, using prediction intervals calculation for the selected calibration functions. Measurement Uncertainty (MU) was also estimated, allowing the final choice of the calibration function to be used for quality control, giving the most fit for purpose performance level in accordance with the product specifications. As Life Cycle Management of the method also includes its routine use, the Measurement Uncertainty was checked on spiked and unspiked extract samples with different dilution levels, in order to verify the accordance of results between spiked and unspiked samples and to prepare a replication strategy to be applied during the routine use of the method.


Asunto(s)
Compuestos de Bifenilo/metabolismo , Cromatografía Líquida de Alta Presión/métodos , Cromatografía en Capa Delgada/métodos , Glucósidos , Fenoles , Picratos/metabolismo , Plantago/química , Compuestos de Bifenilo/química , Glucósidos/análisis , Glucósidos/química , Glucósidos/metabolismo , Límite de Detección , Modelos Lineales , Fenoles/análisis , Fenoles/química , Fenoles/metabolismo , Picratos/química , Extractos Vegetales/química , Reproducibilidad de los Resultados
3.
Ultrason Sonochem ; 78: 105709, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34419864

RESUMEN

In this work, high frequency and low power ultrasound without external heating source and mechanical stirring in biodiesel production were studied. Transesterification of soybean oil with methanol and catalyzed by KOH was investigated using ultrasound equipment and ultrasonic transducer. The effect of ultrasonic output power (3 W-9 W), ultrasonic frequency (1 MHz and 3 MHz), and alcohol to oil molar ratio (6:1 and 8:1) have been investigated. The increase in ultrasonic power provided higher conversion rates. In addition, higher conversion rates were obtained by increasing the ultrasonic frequency from 1 MHz to 3 MHz (48.7% to 79.5%) for the same reaction time. Results also indicate that the speed of sound can be used to evaluate the produced biodiesel qualitatively. Further, the ultrasound system presented electric consumption (46.2W∙h) four times lower than achieved using the conventional method (211.7W∙h and 212.3W∙h). Thus, biodiesel production using low power ultrasound in the MHz frequency range is a promising technology that could contribute to biodiesel production processes.


Asunto(s)
Aceite de Soja , Biocombustibles , Catálisis , Esterificación , Etanol , Calefacción , Aceites de Plantas , Ultrasonido
4.
Nutrients ; 13(2)2021 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-33525653

RESUMEN

Currently the 25-hydroxy vitamin D (25(OH)D) concentration is thought to be the best estimate of the vitamin D status of an individual. Unfortunately, its measurement remains complex, despite recent technological advances. We evaluated the biological variation (BV) of 25(OH)D in order to set analytical performance specifications (APS) for measurement uncertainty (MU). Six European laboratories recruited 91 healthy participants. The 25(OH)D concentrations in K3-EDTA plasma were examined weekly for up to 10 weeks in duplicate on a Lumipulse G1200 (Fujirebio, Tokyo, Japan). The linear regression of the mean 25(OH)D concentrations at each blood collection showed that participants were not in a steady state. The dissection of the 10-sample collection into two subsets, namely collections 1-5 and 6-10, did not allow for correction of the lack of homogeneity: estimates of the within-subject BV ranged from 5.8% to 7.1% and the between-subject BV ranged from 25.0% to 39.2%. Methods that would differentiate a difference induced by 25(OH)D supplementation at p < 0.05 should have MU < 13.6%, while at p < 0.01, the MU should be <9.6%. The development of APS using BV assumes a steady state of patients. The findings in this study suggest that patients are not in steady state. Therefore, APS that are based on MU appear to be more appropriate.


Asunto(s)
Vitamina D/análogos & derivados , Recolección de Muestras de Sangre , Humanos , Modelos Lineales , Modelos Teóricos , Incertidumbre , Vitamina D/análisis , Vitamina D/sangre
5.
J Pharm Biomed Anal ; 181: 113051, 2020 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-31962246

RESUMEN

It is the objective of a systematic and holistic Quality-by-Design approach to demonstrate and ensure that an analytical procedure is fit for its intended purpose over its entire lifecycle. Such a lifecycle approach, as proposed for a new USP General Information Chapter includes the three stages Procedure Design and Development, Procedure Performance Qualification, and Continued Procedure Performance Verification, in alignment to manufacturing process validation. A decisive component of this approach is the Analytical Target Profile, which defines the performance requirements for the measurement of a Quality Attribute as the target for selection, development and optimization of the respective analytical procedures. Although the most benefit can be gained by a comprehensive Quality-by-Design approach establishing the Analytical Target Profile in the very beginning of a drug development project, it may also be established retrospectively for analytical procedures long in routine use, in order to facilitate future lifecycle activities such as continual improvements, transfers, monitoring and periodic performance evaluations. In contrast to the first two stages of the analytical lifecycle with usually limited amount of data, the Continued Procedure Performance Verification stage offers the possibility to utilize a much more reliable data base to collect, analyze, and evaluate data that relate to analytical procedure performance. This monitoring program should be aligned as far as possible with other quality systems already in place and may include performance indicators such as Conformity (i.e. out-of specification test results with analytical root-cause), Validity (i.e. failure to meet method acceptance criteria, e.g. system suitability tests), and (numerical) analytical performance parameters (e.g. ranges for replicate determinations, control sample results, etc). In addition to the monitoring of analytical control parameters by means of control charts, average (pooled) performance parameters can be calculated. Over time, a large number of data can be included and thus the reliability of these estimates is increased tremendously. Such reliable estimates for the true performance parameters, e.g. repeatability or intermediate precision are essential to identify systematic effects (also called special cause variation) with good confidence. The intent of the analytical procedure performance evaluation is to identify substandard performance, identify root cause through investigations, and determine when additional activities are required to improve it. Examples are provided for the monitoring and evaluation of performance parameters for the compendial drug substance Furosemide and for biopharmaceutical applications.


Asunto(s)
Composición de Medicamentos/normas , Investigación Farmacéutica/organización & administración , Vigilancia de Productos Comercializados/métodos , Control de Calidad , Proyectos de Investigación , Investigación Farmacéutica/métodos , Reproducibilidad de los Resultados
6.
Clin Chem Lab Med ; 58(2): 240-250, 2020 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-31469649

RESUMEN

Background Despite that measurement uncertainty data should facilitate an appropriate interpretation of measured values, there are actually few reported by clinical laboratories. We aimed to estimate the measurement uncertainty of some ß-lactam antibiotics (ß-LA), and to evaluate the impact of reporting the measurement uncertainty on clinicians' decisions while guiding antibiotic therapy. Methods Measurement uncertainty of ß-LA (aztreonam [ATM], cefepime [FEP], ceftazidime [CAZ], and piperacillin [PIP]) values, obtained by an UHPLC-MS/MS based-method, was estimated using the top-down approach called the single laboratory validation approach (EUROLAB guidelines). Main uncertainty sources considered were related to calibrators' assigned values, the intermediate precision, and the bias. As part of an institutional program, patients with osteoarticular infections are treated with ß-LA in continuous infusion and monitored to assure values at least 4 times over the minimal inhibitory concentration (4×MIC). We retrospectively evaluated the impact of two scenarios of laboratory reports on clinicians' expected decisions while monitoring the treatment: reports containing only the ß-LA values, or including the ß-LA coverage intervals (ß-LA values and their expanded measurement uncertainties). Results The relative expanded uncertainties for ATM, FEP, CAZ and PIP were lower than 26.7%, 26.4%, 28.8%, and 25.5%, respectively. Reporting the measurement uncertainty, we identified that clinicians may modify their decision especially in cases where 4×MIC values were within the ß-LA coverage intervals. Conclusions This study provides a simple method to estimate the measurement uncertainty of ß-LA values that can be easily applied in clinical laboratories. Further studies should confirm the potential impact of reporting measurement uncertainty on clinicians' decision-making while guiding antibiotic therapy.


Asunto(s)
Antibacterianos/sangre , Monitoreo de Drogas/métodos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Aztreonam/sangre , Enfermedades Óseas Infecciosas/tratamiento farmacológico , Cefepima/sangre , Cromatografía Líquida de Alta Presión , Humanos , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa/efectos de los fármacos , Estudios Retrospectivos , Espectrometría de Masas en Tándem , Incertidumbre
7.
Food Chem ; 246: 323-327, 2018 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-29291856

RESUMEN

This study investigated a method for validating and determining the measurement uncertainty for the composition of brominated vegetable oil (BVO) in soft drinks and carbonated waters commonly consumed in South Korea. First, we studied a simple and precise qualitative colorimetric method at the maximum residues level 15 ppm. And an analytical method using ion chromatography (IC) was validated and identified with brominated fatty acids by gas chromatography electron ionization mass spectrometry (GC/EI-MS). The measurement uncertainty was evaluated based on the precisional study and confirmed by the preliminary inter-laboratory study. For IC analysis, the recovery range of BVO was from 97.8% to 107.2% with relative standard deviations between 0.18% and 0.69%. In addition, the expanded uncertainty of the BVO was 1.59. These results indicate that the validated method is appropriate for identifying of BVO and can be used to verify the safety of soft drinks or carbonated waters containing BVO residues.


Asunto(s)
Bebidas Gaseosas/análisis , Agua Carbonatada/análisis , Halogenación , Aceites de Plantas/análisis , Ácidos Grasos , Inocuidad de los Alimentos/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Aceites de Plantas/química , Control de Calidad , Reproducibilidad de los Resultados , República de Corea , Incertidumbre
8.
Anal Bioanal Chem ; 409(26): 6069-6080, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28808779

RESUMEN

A gas chromatography-isotope dilution mass spectrometry (GC-IDMS) technique was developed for the quantification of two heavy polyaromatic hydrocarbons (PAHs), benz[a]anthracene and benzo[a]pyrene, in yerba maté tea (maté). The optimisation of two extraction methods, namely liquid-liquid extraction and accelerated solvent extraction, was carried out. Both optimised methods were validated using a certified reference material of fine dust and the results were within the expanded uncertainties at 95% confidence level. Recoveries of 99.2-106.7% with RSD of measurements of 1.1-2.3% were achieved for benz[a]anthracene. Recoveries of 95.7-101.9% with RSD of measurements of 0.4-1.4% were achieved for benzo[a]pyrene. The validated methods were applied for the extraction of benz[a]anthracene and benzo[a]pyrene in maté powder from NIST. A metrological approach was undertaken to ensure the traceability of measurement results. The uncertainties associated with the results were rigorously evaluated and also reported herein. Graphical abstract Quantification of benz[a]anthracene and benzo[a]pyrene using IDMS.


Asunto(s)
Benzo(a)Antracenos/análisis , Benzo(a)pireno/análisis , Ilex paraguariensis/química , Extracción Líquido-Líquido/métodos , Espectrometría de Masas/métodos , Tés de Hierbas/análisis , Benzo(a)Antracenos/aislamiento & purificación , Benzo(a)pireno/aislamiento & purificación , Isótopos de Carbono/análisis , Isótopos de Carbono/aislamiento & purificación , Contaminación de Alimentos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Técnicas de Dilución del Indicador
9.
Food Chem ; 213: 19-25, 2016 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-27451150

RESUMEN

This study investigated a method for the validation and determination of measurement uncertainty for the simultaneous determination of synthetic phenolic antioxidants (SPAs) such as propyl gallate (PG), octyl gallate (OG), dodecyl gallate (DG), 2,4,5-trihydroxy butyrophenone (THBP), tert-butylhydroquinone (TBHQ), butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT) in edible oils commonly consumed in Korea. The validated method was able to extract SPA residues under the optimized HPLC-UV and LC-MS/MS conditions. Furthermore, the measurement of uncertainty was evaluated based on the precision study. For HPLC-UV analysis, the recoveries of SPAs ranged from 91.4% to 115.9% with relative standard deviations between 0.3% and 11.4%. In addition, the expanded uncertainties of the SPAs ranged from 0.15 to 5.91. These results indicate that the validated method is appropriate for the extraction and determination of SPAs and can be used to verify the safety of edible oil products containing SPAs residues.


Asunto(s)
Antioxidantes/química , Análisis de los Alimentos/métodos , Fenoles/química , Aceites de Plantas/química , Hidroxianisol Butilado/química , Hidroxitolueno Butilado/química , Calibración , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Ácido Gálico/análogos & derivados , Ácido Gálico/química , Hidroquinonas/química , Galato de Propilo/química , Reproducibilidad de los Resultados , República de Corea , Espectrofotometría Ultravioleta , Espectrometría de Masas en Tándem , Incertidumbre
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