Accreditation and Quality Assurance最新文献

Accurate reticulocyte enumeration is essential for the diagnosis and management of anemia, directly influencing clinical decisions and patient care. This study aimed to develop and validate a national external quality assessment program for manual reticulocyte counting in Thailand. A pilot program was implemented at the Faculty of Associated Medical Sciences, Chiang Mai University, employing reticulocyte control materials prepared via new methylene blue staining, formaldehyde fixation, and mounting with synthetic resin. The control slides were rigorously evaluated for homogeneity and stability in accordance with international quality standards. Fifty clinical laboratories participated in two assessment cycles, each receiving duplicate samples for analysis. Performance was evaluated using robust statistical metrics and a standardized proficiency scoring system. The reticulocyte slides demonstrated excellent homogeneity and maintained stability during transport and storage. Results showed that more than 90% of laboratories engaged in both cycles, and all participants achieved excellent proficiency scores, reflecting a high standard of manual reticulocyte enumeration nationwide. Error analysis identified most issues as related to cell counting technique and clerical processes, which were addressed through focused technical training and process improvements. The implementation of this quality assessment scheme has strengthened laboratory capacity and fostered greater confidence in reticulocyte testing across Thailand. Continued participation and ongoing education are recommended to sustain high performance and ensure continued alignment with international best practices in laboratory hematology.

In the manufacturing process of pesticide formulations, quality control plays a crucial part in ensuring its effectiveness and meeting requirements of regulatory for safe use. In this paper, a simplified HPLC-based method has been developed for simultaneous quantitative determination of Pyriproxyfen and Bifenthrin in 10% EC formulation using a C-18 analytical column (150 mmX4.6 mmX5 µm). Based on chromatographic separation with good resolution, acetonitrile: water (80:20, v/v) was selected as mobile phase in isocratic mode with a flow rate of 1.2 mL/min at a constant column temperature of 30 °C and UV detection at 220 nm. The method was validated in line with SANCO/3030/99 rev. 5 guidelines encompassing the key parameters system suitability, linearity, precision, recovery, LOD & LOQ. The validation parameters were found within acceptance criteria. The LOD and LOQ for Pyriproxyfen was 8.6 mg/L and 26.0 mg/L while that of Bifenthrin was 10.0 mg/L and 30.0 mg/L, respectively. Precision with acceptable %RSD of < 2% and recoveries ranging from 80 to 120% were obtained. Further escorting the decision making and confidence in the reliability of the produced data, measurement uncertainty using Eurachem/ CITAC procedure were obtained. The contributions to the uncertainty of measurement were from sample preparation, calibration standards preparation, calibration curve, and purity data. The contribution to the uncertainty of measurement from the analysis by HPLC were repeatability and intra-lab reproducibility. The combined expanded uncertainty of measurement was between 0.15% and 0.19%. The proposed analytical method is suitable for simultaneous quantitative determination of pyriproxyfen and bifenthrin in respective formulations.

Pulses are a common vegetable and grain in the human diet because of their high protein content. The use of pesticides for control is impacted by a variety of pests, which eventually leads to a residue issue in the finished goods. Considering the point, a field trial conducted to study the dissipation of residues of chlorantraniliprole and emamectin benzoate in/on cowpea pods showed initial accumulation of 1.69 and 0.15 mg/kg at the recommended doses of 18.50 SC @ 30 g a.i./ha and 5 SG @ 10 g a.i./ha, respectively. The residues of chlorantraniliprole and emamectin reached below the limit of quantitation (LOQ) of 0.01 mg/kg on the 7th and 5th day, respectively. Both the residues followed first-order kinetics with half-lives of 1.1 and 1.9 days, respectively. A pre-harvest interval (PHI) of 5 days is advised for both pesticides on cowpea when the green pods are to be utilized as human food in order to be safe, according to the current study. Based on theoretical maximum residue contribution (TMRC) and maximum allowed intake (MPI), risk evaluation revealed that TMRC < MPI in every instance.

This study presents the development and validation of a stability-indicating UPLC-MS/MS method for the simultaneous determination of trifluridine, tipiracil hydrochloride and their impurities. The chromatographic separation was achieved on a Waters UPLC using the Acquity BEH Phenyl column (100 mm ×2.1 mm, 1.7 µm) with a mobile phase comprising methanol and ammonium formate buffer (50:50, v/v) at a flow rate of 0.5 mL/min. The detection was carried out at the wavelength of 257 nm. The validation of the developed method adhered to ICH guidelines, evaluating parameters such as specificity, linearity, precision, accuracy, robustness and forced degradation. The method exhibited excellent linearity (R² > 0.999), high precision (%RSD < 1%) and recoveries ranging from 99.54% to 100.90%. The method was demonstrated to be robust against variations in flow rate and mobile phase composition, showing reproducibility across analysts. Forced degradation studies under acidic, alkaline, oxidative, thermal, photolytic and hydrolytic conditions confirmed the method’s stability-indicating capability. Degradation products were identified and characterized using LC–MS/MS, providing enhancing its application for stability testing, which is crucial for ensuring the quality, safety and efficacy of pharmaceutical  formulations. The developed method has been reported to be reliable and suitable for routine analysis of trifluridine, tipiracil hydrochloride and their impurities/related substances in both bulk drug and dosage forms.

The study presents method development, optimization, and validation of RP-HPLC technique to measure dobutamine, a cardiotonic agent utilized in the treatment of acute heart failure and cardiogenic shock. An Analytical Quality by Design was used to optimize chromatographic parameters, such as composition of the mobile phase, flow rate, and temperature of the column, applied Central Composite Design. The resulting optimized procedure showed superior system suitability, consisting of tailing factor 1.0, number of plates 12036 and similarity factor of 98.9 percent, which was very high in terms of resolution and reproducibility. The six repeated injections used to measure the system precision were 2106, 310.67 in terms of mean peak area and the low %RSD was 0.3 which indicated a high reproducibility. According to forced degradation studies, dobutamine was found to be stable when exposed to acidic conditions, basic conditions and peroxide conditions and also under thermal conditions; though these findings were accompanied by a high photolytic degradation (9%) and thus need to be stored under light protection. The technique also showed linearity over the broad concentration range (50 %, 150 %) with an R² of 0.99996 and at three different concentrations of 50 %, 100 %, and 150 %, the recovery studies have shown accurate results with low %RSD values (0.2, 0.4). The robustness assurance ensured that there is minimum change in USP tailing, plate counts and % similarity factor with different chromatographic conditions hence robustness of this methodology. The standardized AQbD-informed RP-HPLC method exhibits great precision, accuracy, and reliability in the analysis of dobutamine during the pharmaceutical quality control with the ICH compliance, contributing to the safety of patients by the guarantee of consistent therapeutic efficacy.

Biomethane is expected to be important in meeting Europe’s greenhouse gas reduction target. The composition of biomethane varies, therefore, depending on the feedstock and process parameters. The European standards EN 16723 specify requirements for injecting biomethane into natural gas networks and its use as vehicle fuel. Ensuring that biomethane composition complies with the requirements set in the standards requires rigorous quality control processes and validated analytical methods. Method validation for parties lacking practical experience or training can be a complex process involving numerous steps and requires adequate guidelines, which were lacking for biomethane. The BiometCAP project has, therefore, developed a standardized protocol for evaluating gas analyzers in biomethane applications with detailed procedures for assessing instrument performance and ensuring accurate and reliable measurements. This article describes how to use the validation protocol with practical applications for evaluating the limit of detection and limit of quantification, the working range and linearity, the precision, the bias and finally to calculate the measurement uncertainties using the analytical method described in ISO 2620:2024 as an example. This method based on TD-CG/MS-FID can therefore be considered fit-for-purpose, providing reliable, precise and sensitive measurements for the analysis of VOCs as demonstrated for 3-carene, dichloromethane and hexamethyldisiloxane. Finally, the article also summarizes the measurement uncertainties obtained during an extensive evaluation exercise organized between seven NMIs across Europe. For any future validation work, measurement uncertainties of 1 to 10% relative for any regulated compounds can be used as reference.

The goal is to create an RP-HPLC technique that is easy to utilize, quick, and specific enough to measure Abiraterone and Niraparib in bulk and prescription dose forms using Box–Behnken response surface design with application to dissolution studies. Optimization was performed by Box–Behnken design with selecting mobile phase ratio of volume of acetonitrile, volume of trifluoroacetic acid, and flow rate as factors and evaluating responses, namely, retention time and tailing factor through Symmetry C18 column (150 × 4.6 mm, 3.5 µm) with a mobile phase of acetonitrile: 0.1% TFA (40:60 v/v) at a flow rate of 1 mL/min, detection at 257 nm, and a runtime of 6 min. Box–Behnken design compared the effect of flow rate, ratio of acetonitrile, and volume of TFA on retention time and tailing factor, and optimized conditions for increased sensitivity. Retention times were 2.013 min for Abiraterone and 3.655 min for Niraparib. The technique was found to be excellent in linearity with correlation coefficients (R²) of 0.999 for both drugs. Validation parameters such as system suitability, accuracy, precision, linearity, specificity, robustness, LOD, and LOQ were in compliance with ICH guidelines. Forced degradation and dissolution studies established the stability-indicating nature of the method and applicability for release profiling. This technique is an important improvement in the field of pharmaceutical analysis, providing a robust platform for antineoplastic drug development research and quality control.

Graphical abstract

The contemporary development of the society is characterized by a rapid and intensive development of technology and industry, which leads to the appearance of an increasing amount of different products, but also to environmental pollution as product of their work. In everyday life, before placing products on the market, it is necessary to test them. These tests are conducted by testing laboratories in accordance with the relevant specifications for the given products. In case these tests are performed in laboratories accredited to ISO/IEC 17025:2017 ‘General requirements for the competence of testing and calibration laboratories’, by an accreditation body in a country that is a signatory to the ILAC Mutual Recognition Arrangement, their results will be recognized internationally. The basic goal of this paper is to present the current state of accredited laboratories in the Republic of Serbia, i.e., the analysis of the first accreditations granted, the distribution of laboratories by cities in Serbia, the number of testing methods in accredited laboratories, as well as the subject of testing/calibration in them. In addition, statistical multivariate analyses—Pearson’s correlation matrix and principal component analysis—were performed to determine the correlation between accredited laboratories and socio-political parameters, as well as the similarity in the distribution of accredited organizations in Serbia. The results show that the Republic of Serbia has a fairly developed area of quality infrastructure, that there is a certain relation between the granting of initial accreditation and certain socio-political events, as well as that there is a linear dependence between the number of accredited testing and calibration laboratories and the socio-economic parameters of the city. In Serbia, a largest number of accredited testing laboratories analyze media from the environment; however, a large number of those that deal with the testing of materials, food and industrial equipment are also present.

Reference material is of great significance to the measurement accuracy of X-ray energy/wave dispersive spectrometer (EDS/WDS). In this work a reference material of manganese (Mn) content (mass fraction, %) of pure Mn flake for EDS/WDS calibration was developed. The surfaces of Mn flakes were finely treated by mechanical grinding and argon ion polishing, and the Mn flakes with high cleanliness and low roughness were obtained. The homogeneity and stability of Mn content of the Mn flakes were analyzed carefully using electron probe micro-analyzer (EPMA). The Mn content of the reference material was determined using inductively coupled plasma optical emission spectrometer (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). The sources of uncertainty components of Mn reference material were fully analyzed and evaluated. The results show that the homogeneity of the pure Mn flake reference material meet the requirements. The Mn content of the vacuum-packed pure Mn flake is stable for up to one year at ambient temperature. The Mn content reference material of the pure Mn flake reference material is 99.5 %, and its expanded uncertainty is 0.9 % (k = 2). The pure Mn flake reference material can meet the calibration requirements of X-ray EDS/WDS, and guarantee the accuracy and consistency of measurement results. The content of this study complies with the definition of reference materials in ISO 17034 and can be used to calibrate measurement systems. The Mn content reference material can be widely used for element measurement in the fields of scientific research, manufacturing and trade activities.

Graphical abstract

This study allowed us to establish a procedure for determining the pH of seawater by the primary method using cell without junction (Harned cell) in artificial seawater without sulfate ASW-SO₄ which is taken as a reference buffer solution featuring the natural seawater at salinity 35 and an ionic strength equal to ({0.6731text{ mol kg}}^{-1}). The determination of the coefficient average activity ((gamma pm HCl)) of HCl was taken from two approaches. The first one is an experimental approach in which we introduced the potential standard value ((E^circ )) calculated in dilute media. In the second approach, we applied and adapted the Pitzer model in function of the temperature (15, 25 and 35 °C) taking into account all the parameters of the solution in ionic interactions and we demonstrated its feasibility for the solution ASW-SO₄. The choice was made for the first option which was preferred because of its simpler implementation.