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Idelalisib is a phosphatidylinositol 3-kinase delta inhibitor approved by the FDA and the EMA for the treatment of lympholytic lymphoma, B cell non-Hodgkin lymphoma, and lymphocytic lymphoma. The present report describes the validation of a simple, rapid, sensitive, and cost-effective zero-order and first-order derivative spectrophotometric method for the estimation of idelalisib in bulk and in its marketed formulation. Preliminary spectrophotometric analysis of the drug was carried out in methanol and a total of 12 parametric variations were considered. Three selected method variants employing peak-zero and peak-peak techniques were assessed for their stability indicating potential in stress degraded solutions of the drug. The developed method was validated with respect to linearity, accuracy, precision, and robustness. Excellent linearity was observed within the concentration range 1.0–60.0 μg/mL with a correlation coefficient of 0.9997. The limits of assay detection values were found for the range 0.42–3.11 μg/mL, and quantitation limits ranged from 1.29 to 9.42 μg/mL for the proposed method variants. The proposed method was used to quantify the drug in its marketed tablet formulation, and good recoveries ranging from 95.98 to 98.81% were obtained. [ABSTRACT FROM AUTHOR]

Appropriate data collection and using reliable and accurate procedures are the first steps in conducting an experiment that will provide trustworthy outcomes. It is key to perform an assertive statistical analysis and data visualization for a correct interpretation and communication of results. A clear statistical summary and presentation of the data is critical for the reader to easily process and comprehend experimental results. Nowadays, there are a series of different tools to perform proper statistical analysis and create elaborate graphs that will help readers to understand the data, identify trends, detect outliers, evaluate statistical outputs, etc. However, researchers that are beginning to navigate experiments do not frequently encounter a guide that can provide basic principal concepts to begin their statistical analysis and data presentation. Therefore, the objective of this article is to provide a guide or manual to analyze and presents results focused on different types of common food safety experiments, including method comparisons, intervention studies, pathogen presence experiments, bio-mapping, statistical process control, and shelf life experiments. This review will provide information about data visualization options and statistical analysis approaches for different food safety experiments. In addition, basic concepts about descriptive statistics and possible solutions for issues related to microbiological measurements will be discussed. [ABSTRACT FROM AUTHOR]

Biosensors function as sophisticated devices, converting biochemical reactions into electrical signals. Contemporary emphasis on developing biosensor devices with refined sensitivity and selectivity is critical due to their extensive functional capabilities. However, a significant challenge lies in the binding affinity of biosensors to biomolecules, requiring adept conversion and amplification of interactions into various signal modalities like electrical, optical, gravimetric, and electrochemical outputs. Overcoming challenges associated with sensitivity, detection limits, response time, reproducibility, and stability is essential for efficient biosensor creation. The central aspect of the fabrication of any biosensor is focused towards forming an effective interface between the analyte electrode which significantly influences the overall biosensor quality. Polymers and macromolecular systems are favored for their distinct properties and versatile applications. Enhancing the properties and conductivity of these systems can be achieved through incorporating nanoparticles or carbonaceous moieties. Hybrid composite materials, possessing a unique combination of attributes like advanced sensitivity, selectivity, thermal stability, mechanical flexibility, biocompatibility, and tunable electrical properties, emerge as promising candidates for biosensor applications. In addition, this approach enhances the electrochemical response, signal amplification, and stability of fabricated biosensors, contributing to their effectiveness. This review predominantly explores recent advancements in utilizing macrocyclic and macromolecular conjugated systems, such as phthalocyanines, porphyrins, polymers, etc. and their hybrids, with a specific focus on signal amplification in biosensors. It comprehensively covers synthetic strategies, properties, working mechanisms, and the potential of these systems for detecting biomolecules like glucose, hydrogen peroxide, uric acid, ascorbic acid, dopamine, cholesterol, amino acids, and cancer cells. Furthermore, this review delves into the progress made, elucidating the mechanisms responsible for signal amplification. The Conclusion addresses the challenges and future directions of macromolecule-based hybrids in biosensor applications, providing a concise overview of this evolving field. The narrative emphasizes the importance of biosensor technology advancement, illustrating the role of smart design and material enhancement in improving performance across various domains. [ABSTRACT FROM AUTHOR]

Norovirus (NoV) in oysters is a food safety risk of much concern. In order to assess the risk of the exposure, the distribution of the number of NoV copies contained in each oyster should be acquired first for comprehensively quantifying the associated risks. However, the part of the distribution below the limit of quantification cannot be obtained directly by laboratory detecting methods, which hampers accurate assessment. To tackle this challenging problem, a systematic method (Distribution Inference Method by Pooled Sampling) is proposed to infer the unobservable part of distribution based upon all measurements of the pooled samples with n = 2. Using convolutional integrals and real‐coded genetic algorithm for inferring, this method has neither requirements for the type or properties of the original distribution, nor requirements for historical data, even nor requirements for the relationship between observable and unobservable parts of the distribution. A series of experiments were conducted on simulated datasets of a variety of types, including normal distribution, uniform distribution, gamma distribution, lognormal distribution, zero‐inflated Poisson distribution, their combinations, and even their splicing, covering common distribution types in oyster NoV scenario and more general scenarios. The results show that almost all inferred simulation data and their original counterparts passed Kolmogorov–Smirnov tests, which implies that they are essential of the same distribution. Based on this method, a ready‐to‐use web system was developed for researchers to infer their original distribution with pooled‐sampling measurements from the detection of NoV or even other substances. [ABSTRACT FROM AUTHOR]

In the present work, an efficient isocratic HPLC method was developed for the precise and accurate estimation of vitamin D3 in tablet form. The chromatographic conditions comprised an L3 silica column (5 µm in particle size, 4.6 mm × 250 mm) with a mobile phase n-hexane/ethyl acetate (85:15 v/v) with a flow rate of 2.0 mL/min and a detection wavelength of 292 nm. The new methodology was validated for accuracy, precision, specificity, robustness, and quantification limits according to an official monograph of USP/BP and ICH guidelines. The peak areas of the six replicates of the homogeneous sample were recorded. The mean value obtained was 67,301, and the relative standard deviation (RSD) was 0.1741. The linearity and range were in the acceptable bounds, i.e., 0.999, which was calculated using regression line analysis. The results show that the method is truly acceptable as the RSD, as the flow rate was 0.81%, while for the mobile phase composition, it was 0.72%, which lies in the acceptable range. The limit of detection (LOD) and the limit of quantification (LOQ) values were 0.0539 µg/mL and 0.1633 µg/mL, respectively. The % RSD of the intra and inter-day precision of the method was deemed acceptable according to the international commission for harmonization guidelines. The developed method has potential to be used for the detection and quantification of vitamin D3 during routine analysis for tablets in dosage form. [ABSTRACT FROM AUTHOR]

Accurate non-destructive assessment of biomass energy properties is essential for optimizing its use as an alternative fuel. In this study, 200 biomass samples were used to determine higher heating value (HHV) and 120 biomass samples for analyzing ultimate analysis parameters using near-infrared spectroscopy within the full wavenumber range of 12489.48 – 3594.87 cm-1. The samples were grounded, and five different types of partial least squares regression (PLSR) models were developed using traditional preprocessing, multi-preprocessing (MP) with 5 range, MP with 3 range, genetic algorithm, and successive projection algorithm. Limit of detection (LOD) and quantification (LOQ) were calculated using the best-performing model among five different PLSR models for HHV in kJ/kg, as well as the weight percentage (wt.%) of carbon (C), oxygen (O), hydrogen (H), and nitrogen (N). The LOD and LOQ for HHV were calculated as 622.42 kJ/kg and 1886.13 kJ/kg, respectively. Additionally, LOD and LOQ for ultimate analysis parameters, including C, O, H, and N were calculated as: 3.24 weight percentage (wt.%) and 9.81 wt.% for C, 2.04 wt.% and 6.18 wt.% for O, 0.35 wt.% and 1.05 wt.% for H, and 0.22 wt.% and 0.68 wt.% for N. The LOD and LOQ values for HHV, C, O, and H were lower than the minimum reference values used for model development, demonstrating the models’ high sensitivity and potential to reliably detect and precisely quantify these parameters. However, the LOD and LOQ values exceeded the minimum reference value used during model development for the N, indicating that the selected models have certain limitations in assessing the N content in biomass. The sample range should be expanded for wt.% of N to enhance the model’s performance, surpassing the LOD and LOQ values. This will improve the overall sensitivity of the model for reliable detection and quantification of N content in biomass samples.

Abstract The analysis of environmental DNA (eDNA) is becoming integrated as an established biomonitoring tool, often characterized by detection limits exceeding those of conventional counterparts. However, further improving the sensitivity of these methods may be invaluable for the early detection of invasive species, or for locating remnant populations of endangered species, and the adequate quantification of their abundances. In this study, we provide empirical evidence showing that the implementation of multiple genetic markers targeting different loci is a surprisingly overlooked strategy to increase the sensitivity of single‐species detections and quantification of their abundance, particularly at the lower end of the species abundance range. We analyzed 45 natural eDNA samples obtained from a wide range of water bodies in Belgium, in which either the invasive American bullfrog (Lithobates catesbeianus) or the rare European weather loach (Misgurnus fossilis) occurred under variable abundances, and compared detection success and precision of quantification of simplex (single locus) versus multiplex (multilocus) droplet digital PCR (ddPCR) analyses. Multiplexing different primer/probe assays targeting independent loci resulted in a significantly enhanced detection probability compared to the simplex analyses, gaining a twofold reduction in the limit of detection (LOD). Also the precision of eDNA quantification significantly improved in multiplex reactions, especially in low concentration samples. This was reflected in a significant reduction in the coefficient of variation (CV) among technical replicates, resulting in an associated decrease of the limit of quantification (LOQ). We conclude that the use of multiple markers can significantly improve the analytical sensitivity of eDNA‐based single‐species detections and precision of absolute abundance quantifications.

Appropriate data collection and using reliable and accurate procedures are the first steps in conducting an experiment that will provide trustworthy outcomes. It is key to perform an assertive statistical analysis and data visualization for a correct interpretation and communication of results. A clear statistical summary and presentation of the data is critical for the reader to easily process and comprehend experimental results. Nowadays, there are a series of different tools to perform proper statistical analysis and create elaborate graphs that will help readers to understand the data, identify trends, detect outliers, evaluate statistical outputs, etc. However, researchers that are beginning to navigate experiments do not frequently encounter a guide that can provide basic principal concepts to begin their statistical analysis and data presentation. Therefore, the objective of this article is to provide a guide or manual to analyze and presents results focused on different types of common food safety experiments, including method comparisons, intervention studies, pathogen presence experiments, bio-mapping, statistical process control, and shelf life experiments. This review will provide information about data visualization options and statistical analysis approaches for different food safety experiments. In addition, basic concepts about descriptive statistics and possible solutions for issues related to microbiological measurements will be discussed.

Accurate non-destructive assessment of biomass energy properties is essential for optimizing its use as an alternative fuel. In this study, 200 biomass samples were used to determine higher heating value (HHV) and 120 biomass samples for analyzing ultimate analysis parameters using near-infrared spectroscopy within the full wavenumber range of 12489.48 - 3594.87 cm-1. The samples were grounded, and five different types of partial least squares regression (PLSR) models were developed using traditional preprocessing, multi-preprocessing (MP) with 5 range, MP with 3 range, genetic algorithm, and successive projection algorithm. Limit of detection (LOD) and quantification (LOQ) were calculated using the best-performing model among five different PLSR models for HHV in kJ/kg, as well as the weight percentage (wt.%) of carbon (C), oxygen (O), hydrogen (H), and nitrogen (N). The LOD and LOQ for HHV were calculated as 622.42 kJ/kg and 1886.13 kJ/kg, respectively. Additionally, LOD and LOQ for ultimate analysis parameters, including C, O, H, and N were calculated as: 3.24 weight percentage (wt.%) and 9.81 wt.% for C, 2.04 wt.% and 6.18 wt.% for O, 0.35 wt.% and 1.05 wt.% for H, and 0.22 wt.% and 0.68 wt.% for N. The LOD and LOQ values for HHV, C, O, and H were lower than the minimum reference values used for model development, demonstrating the models' high sensitivity and potential to reliably detect and precisely quantify these parameters. However, the LOD and LOQ values exceeded the minimum reference value used during model development for the N, indicating that the selected models have certain limitations in assessing the N content in biomass. The sample range should be expanded for wt.% of N to enhance the model's performance, surpassing the LOD and LOQ values. This will improve the overall sensitivity of the model for reliable detection and quantification of N content in biomass samples. [ABSTRACT FROM AUTHOR]

Use of agro-chemicals in forage crops is restricted due to the fear of direct toxicity to livestock and risk of pesticide residue accumulation in the food chain. Wheat and barley can be used as green fodder and silage, and herbicide residue estimation in green fodder and silage is important for ensuring the safety of dairy cattle. A field experiment was conducted for two years to study pendimethalin residues in the green fodder and silage of wheat and barley. In both cereal crops, pendimethalin (1.125 kg a.i./ha) was applied as pre-emergence along with an unsprayed control. Pendimethalin residues in fodder, silage, and soil were estimated using gas chromatographytandem mass spectrometry (GC-MS/MS). At harvest, pendimethalin residues in fodder and silage of wheat and barley were below the limit of quantification (<0.01 mg/kg) during both crop seasons. Pendimethalin can be safely used for weed control in winter cereals grown for fodder and silage. [ABSTRACT FROM AUTHOR]

The handling of data on food contamination frequently represents a challenge because these are often left-censored, being composed of both positive and non-detected values. The latter observations are not quantified and provide only the information that they are below a laboratory-specific threshold value. Besides deterministic approaches, which simplify the treatment through the substitution of non-detected values with fixed threshold or null values, a growing interest has been shown in the application of stochastic approaches to the treatment of unquantified values. In this study, a multiple imputation procedure was applied in order to analyze contamination data on deoxynivalenol, a mycotoxin that may be present in pasta and pasta substitute products. An application of the proposed technique to censored deoxynivalenol occurrence data is presented. The results were compared to those attained using deterministic techniques (substitution methods). In this context, the stochastic approach seemed to provide a more accurate, unbiased and realistic solution to the problem of left-censored occurrence data. The complete sample of values could then be used to estimate the exposure of the general population to deoxynivalenol based on consumption data. [ABSTRACT FROM AUTHOR]

Efficient detection methods must be developed for 1,4-dioxane due to its suspected status as a human carcinogen, which is highly mobile in food and environmental resources. In this regard, this experiment has been conducted to develop reliable and selective detection and measurement methods by using static headspace (SH) isolation, followed by gas chromatography–mass spectrometry (GC-MS). A new method was developed for determining the spiked 1,4-dioxane contents in a polyethylene glycol 600 (PEG 600). The optimal condition for SH-GC-MS was discussed. The representative ions of 1,4-dioxane and 1,4-dioxane-d8 in the SIM mode of MS are 88 and 96, respectively, and the peaks of the SIM mode were separated and confirmed. The linear range for the method covers 0.25 to 100 mg/L with a coefficient of determination (R2)  ≥  0.999. The method applicability was demonstrated by spike recovery across a variety of food additives (i.e., chlorine bitartrate, choline chloride, polysorbate 20 and 60, and PEG 1000). All spike recovery from the tested samples was in the range of 89.50–102.68% with a precision of 0.44–11.22%. These findings suggest a new analytical method for food safety inspection, and could be applicable for ensuring the safety of foods and environmental and public health on a broad scale. [ABSTRACT FROM AUTHOR]

In the present work, an efficient isocratic HPLC method was developed for the precise and accurate estimation of vitamin D3 in tablet form. The chromatographic conditions comprised an L3 silica column (5 µm in particle size, 4.6 mm × 250 mm) with a mobile phase n-hexane/ethyl acetate (85:15 v/v) with a flow rate of 2.0 mL/min and a detection wavelength of 292 nm. The new methodology was validated for accuracy, precision, specificity, robustness, and quantification limits according to an official monograph of USP/BP and ICH guidelines. The peak areas of the six replicates of the homogeneous sample were recorded. The mean value obtained was 67,301, and the relative standard deviation (RSD) was 0.1741. The linearity and range were in the acceptable bounds, i.e., 0.999, which was calculated using regression line analysis. The results show that the method is truly acceptable as the RSD, as the flow rate was 0.81%, while for the mobile phase composition, it was 0.72%, which lies in the acceptable range. The limit of detection (LOD) and the limit of quantification (LOQ) values were 0.0539 µg/mL and 0.1633 µg/mL, respectively. The % RSD of the intra and inter-day precision of the method was deemed acceptable according to the international commission for harmonization guidelines. The developed method has potential to be used for the detection and quantification of vitamin D3 during routine analysis for tablets in dosage form.

One of the most challenging steps in chemical risk assessment is the dietary exposure due to the high percentage of left-censored data (LCD). Mycotoxins are the group of chemical contaminants known to show the highest percentage of LCD among chemical contaminants. These data are extremely important especially if they are used for the development of new legislations with permitted maximum limits. In this study, we address the importance of analytical techniques and current methods of dealing with LCD, with the goal of highlighting the effect of LCD on risk assessment, which could have a potential impact on future regulations of mycotoxins in foods and the economic implications of such regulations. Thirteen European Food Safety Authority (EFSA) Scientific Opinions and Reports on the risk of mycotoxins to humans were evaluated. The most used analytical method was based on Liquid Chromatography-Mass Spectrometry (LC-MS). Most of the occurrence data for mycotoxins in EFSA risk assessments over the last decade were condensed between 80 and 100% LCD. The typical statistical methods to handle LCD, the substitution method and cut-off values approach, frequently lead to the overestimation of the human risk which can ultimately lead to stricter law regulations with economic implication on the agricultural trades. Understanding the obstacles that analysts face and the type of data that risk assessors require will help to close the uncertainties and gaps that currently exist in exposure and risk assessment. Establishing limits of detections (LODs) and limits of quantification (LOQs) while having a clear data purpose can help reduce uncertainties in risk assessment and provide more meaningful exposure evaluations. [Display omitted] • Most of the occurrence data for mycotoxins in EFSA risk assessments were condensed between 80 and 100% LCD. • The most common statistical methods used to handle LCD may lead to overestimating risk assessment. • There is a need for harmonization between analysts and risk assessors in order to improve data quality. • LODs and LOQs should be set based on the purpose of the data. [ABSTRACT FROM AUTHOR]

ObjectiveA droplet digital polymerase chain reaction （ddPCR） method was developed for the rapid quantitative detection of Listeria monocytogenes in food.MethodsSpecific primers and probes for Listeria monocytogenes were screened. The constant value effect of ddPCR method and plate counting method was compared through the detection of pure bacterial solution and artificially contaminated samples. The specificity， sensitivity and repeatability of ddPCR method were analyzed.ResultsThe ddPCR had the characteristics of excellent specificity， sensitivity and repeatability in Listeria monocytogenes detection. The limit of detection （LOD） and the limit of quantification （LOQ） in pure bacterial solution were 136 CFU/mL. The LOQ in squid ring and sausage samples was 240 CFU/g and 155 CFU/g. The coefficient of variation of ddPCR was less than 25% at each gradient level， and the relative deviation of the logarithm of ddPCR and plate counting was less than 30%.ConclusionThe established ddPCR method is rapid， accurate， sensitive and specific for the quantitative detection of Listeria monocytogenes in food.

In accordance with Article 43 of Regulation (EC) No 396/2005, the European Commission requested EFSA to perform a risk assessment of the existing maximum residues levels (MRLs) for oxamyl considering the new toxicological reference values. Additionally, if needed to ensure adequate consumer protection, lower limits of quantification (LOQs) than those currently established in the legislation should be proposed. EFSA performed various consumer exposure calculation scenarios, considering the risk assessment values as available for the existing uses of oxamyl and the lowering of LOQs for several plant and animal commodities as suggested by the European Union Reference Laboratories for Pesticide Residues (EURLs). Based on the results of the consumer exposure assessment calculated considering the risk assessment values for crops with authorised oxamyl uses and the existing EU MRLs at the LOQ for remaining commodities (scenario 1), chronic consumer intake concerns were identified for 34 diets. Acute exposure concerns were identified for a wide range of crops, including crops with currently authorised oxamyl uses: bananas, potatoes, melons, cucumbers, carrots, watermelons, tomatoes, courgettes, parsnips, salsifies and aubergines/eggplants. Under exposure calculation scenario 3, which considered lowering of all MRLs to the lowest analytically achievable limits of quantification, EFSA concludes that chronic consumer exposure concerns can still not be excluded. Similarly, acute consumer exposure concerns were identified for 16 commodities, including crops with known authorised uses: potatoes, melons, watermelons and tomatoes, even though for these crops a lower LOQ as proposed by the EURLs were considered. Further refinements of the calculated exposure at the current stage were not possible by EFSA, but EFSA identified a list of commodities for which a lower LOQ than routinely achievable is expected to significantly reduce the consumer exposure and for which a risk management decision is required. [ABSTRACT FROM AUTHOR]

A new precise, selective and reliable reversed phase high performance liquid chromatographic (RPHPLC) method has been developed and validated for the determination of Methyl paraben sodium (MPS) and Propyl paraben sodium (PPS) (preservatives) in Iron protein succinylate syrup. Optimized conditions were; Methanol: Water (65: 35) as mobile phase, UV/Vis detector at the wavelength of 254nm and flow rate was set at 1.3 ml min-1. By applying the set of conditions, separation of components was carried out in less than 7 min for both the analytes. The method was validated according to International conference of Harmonization (ICH) guidelines and the analytical characteristic parameters of validation included specificity, limit of detection (LOD), limit of quantification, linearity, accuracy, precision and robustness were evaluated. The calibration curve was found to be linear in the range of 0.045mg mL-1 to 0.075 mg mL-1 for Methyl paraben sodium and 0.015mg mL-1 to 0.025mg mL-1 for propyl paraben sodium with a correlation coefficient r² > 0.999. Accuracy; reported as percentage recovery was found to be in the range of 98.71%-101.64% for Methyl paraben sodium and 99.85%-101.47% for Propyl paraben sodium at 80%, 100% and 120% concentration for both the analytes. The proposed method was found to be precise and robust when evaluated by variations in wavelength, mobile phase composition, temperature and analyst. The limit of detection (LOD) was found 0.001mg mL-1 (3ppm) for Methyl paraben sodium and 0.001mg mL-1 (1ppm) for Propyl paraben sodium. [ABSTRACT FROM AUTHOR]

The development of a new vaccine requires the precise characterization of all the physicochemical parameters of the vaccine antigens, which are the molecules that induce the immune response. Taylor dispersion analysis (TDA) is a promising alternative technique for the determination of diffusion coefficients and hydrodynamic radii of proteins, macromolecules and nanoparticles. In this work, TDA was used to determine the hydrodynamic radius distribution and its average value of four antigens: diphtheria toxoid (DT), tetanus toxoid (TT), hepatitis B surface antigen (HBsAg) and polyribosyl-ribitol phosphate conjugated to tetanus toxoid (PRP-T). The robustness of the results obtained was investigated on bare fused silica capillary and hydroxypropylcellulose coated capillary. The impact of operational parameters on the limit of detection (LOD) and limit of quantification (LOQ) were studied from both theoretical and experimental points of view. The influence of the diameter and the length of the capillary on the LOD and LOQ were studied as well as the impact of the mobilization pressure. General guidelines for the choice of the initial operating conditions are given for the development of future TDA methods.

Abstract In accordance with Article 43 of Regulation (EC) No 396/2005, the European Commission requested EFSA to perform a risk assessment of the existing maximum residues levels (MRLs) for oxamyl considering the new toxicological reference values. Additionally, if needed to ensure adequate consumer protection, lower limits of quantification (LOQs) than those currently established in the legislation should be proposed. EFSA performed various consumer exposure calculation scenarios, considering the risk assessment values as available for the existing uses of oxamyl and the lowering of LOQs for several plant and animal commodities as suggested by the European Union Reference Laboratories for Pesticide Residues (EURLs). Based on the results of the consumer exposure assessment calculated considering the risk assessment values for crops with authorised oxamyl uses and the existing EU MRLs at the LOQ for remaining commodities (scenario 1), chronic consumer intake concerns were identified for 34 diets. Acute exposure concerns were identified for a wide range of crops, including crops with currently authorised oxamyl uses: bananas, potatoes, melons, cucumbers, carrots, watermelons, tomatoes, courgettes, parsnips, salsifies and aubergines/eggplants. Under exposure calculation scenario 3, which considered lowering of all MRLs to the lowest analytically achievable limits of quantification, EFSA concludes that chronic consumer exposure concerns can still not be excluded. Similarly, acute consumer exposure concerns were identified for 16 commodities, including crops with known authorised uses: potatoes, melons, watermelons and tomatoes, even though for these crops a lower LOQ as proposed by the EURLs were considered. Further refinements of the calculated exposure at the current stage were not possible by EFSA, but EFSA identified a list of commodities for which a lower LOQ than routinely achievable is expected to significantly reduce the consumer exposure and for which a risk management decision is required.

The widespread occurrence of clinically relevant antibiotic resistance within humans, animals, and environment motivates the development of sensitive and accurate detection and quantification methods. Metagenomics and quantitative PCR (qPCR) are amongst the most used approaches. In this study, we aimed to evaluate and compare the performance of these methods to screen antibiotic resistance genes in animal faecal, wastewater, and water samples. Water and wastewater samples were from hospital effluent, different treatment stages of two treatment plants, and of the receiving river at the discharge point. The animal samples were from pig and chicken faeces. Antibiotic resistance gene coverage, sensitivity, and usefulness of the quantitative information were analyzed and discussed. While both methods were able to distinguish the resistome profiles and detect gradient stepwise mixtures of pig and chicken faeces, qPCR presented higher sensitivity for the detection of a few antibiotic resistance genes in water/wastewater. In addition, the comparison of predicted and observed antibiotic resistance gene quantifications unveiled the higher accuracy of qPCR. Metagenomics analyses, while less sensitive, provided a markedly higher coverage of antibiotic resistance genes compared to qPCR. The complementarity of both methods and the importance of selecting the bestmethod according to the study purpose are discussed. [ABSTRACT FROM AUTHOR]

Rapid, sensitive, reproducible, and cost-effective zero-order and first-order derivative spectrophotometric method has been developed for the quantification of solifenacin succinate in bulk and its tablet formulation. Preliminary spectrophotometric determination of the drug was carried out in 0.1 N HCl, methanol, and in phosphate buffer pH 2.0 with a total of thirty-three parametric variations. The selected method with three parametric variations employing peak–zero (P–0) and peak–peak (P–P) techniques was assessed for stability, indicating a potential for force-degraded solutions. The method was validated in accordance with the ICH guidelines with respect to linearity, accuracy, precision, limit of detection (LOD), limit of quantification (LOQ), and robustness. Excellent linearity was noted in a concentration range of 1.0–80.0 μg/mL for all three method variants. Limits of detection for the proposed method ranged from 0.03–0.16 μg/mL and limits of quantitation were found to be in the range of 0.09–0.48 μg/mL, respectively. Excellent recovery of the drug was obtained from its marketed tablet formulation with the proposed method. [ABSTRACT FROM AUTHOR]

Efficient detection methods must be developed for 1,4-dioxane due to its suspected status as a human carcinogen, which is highly mobile in food and environmental resources. In this regard, this experiment has been conducted to develop reliable and selective detection and measurement methods by using static headspace (SH) isolation, followed by gas chromatography–mass spectrometry (GC-MS). A new method was developed for determining the spiked 1,4-dioxane contents in a polyethylene glycol 600 (PEG 600). The optimal condition for SH-GC-MS was discussed. The representative ions of 1,4-dioxane and 1,4-dioxane-d8 in the SIM mode of MS are 88 and 96, respectively, and the peaks of the SIM mode were separated and confirmed. The linear range for the method covers 0.25 to 100 mg/L with a coefficient of determination (R2) ≥ 0.999. The method applicability was demonstrated by spike recovery across a variety of food additives (i.e., chlorine bitartrate, choline chloride, polysorbate 20 and 60, and PEG 1000). All spike recovery from the tested samples was in the range of 89.50–102.68% with a precision of 0.44–11.22%. These findings suggest a new analytical method for food safety inspection, and could be applicable for ensuring the safety of foods and environmental and public health on a broad scale.

An efficient gas chromatography–mass spectrometry approach was used in this study to quantify 13 pesticide residues in rooibos teas purchased from registered retail outlets in South Africa between November 2019 and April 2020. A QuEChERS (Quick, easy, cheap, effective, rugged, and safe) procedure was used to extract pesticides using 7.5 mg of graphitized carbon black (GCB), 50 mg of primary secondary amine (PSA), and 150 mg of anhydrous MgSO4. In order to compensate for the matrix effect, matrix matched calibration curves ranging from 10 µg/kg–500 µg/kg were applied for accurate quantification. For validation purposes, accuracy tests were conducted using a blank tea sample spiked with pesticide standards at two different concentrations (10 and 100 μg/kg). Most of the analytes were recovered within acceptable recovery ranges (72–106%), with a relative standard deviation of less than 20%. The limits of quantification were low, all falling below 10 μg/kg which meets the maximum residue limits (MRLs). The validated method was used to analyze 100 tea samples, and among the pesticides analyzed, deltamethrin and lambda-cyhalothrin were detected in only one samples at a concentration (92.11 and 66.41 μg/kg, respectively) below the MRLs stipulated by the European Union. The level of pesticides that are commonly used in tea should be checked often.

In this work, a cyclic voltammetry analysis for the detection of Ascorbic Acid (AA) based on a carbon-clay paste electrode modified with titanium dioxide (CPEA/TiO2) is presented. The electrochemical sensor was prepared using clay and carbon graphite, mixed with TiO2 to investigate the electrode behavior towards the detection of AA. Comprehensive characterization approaches including X-ray diffraction (XRD), Selected area electron diffraction (SAED), Transmission electron microscopy (TEM), Fourier transform infra-red spectroscopy (FTIR) were carried out on different samples. The results indicated that, the electrode has been effectively modified, while the electrochemical parameters of AA on CPEA/TiO2/UV such as the charge transfer coefficient (αa), number of electrons (n) transferred and standard potential were calculated. CPEA/TiO2/UV exhibit better photoactivity and also higher electronic conductivity under light radiation (100 W). The linear range for AA was determined between 0.150μM and 0.850 μM with the straight-line equation equivalent to Ipa(μA)=2.244[AA]+1.234 (n = 8, R2 = 0.993). The limit of detection was 0.732 μM (3σ) and limit of quantification was 2.440 μM. For the analytical applications, pharmaceutical tablets such as Chloroquine phosphate, Azithromycin and Hydroxychloroquine sulfate were performed. In addition, interference study in the analytical application was performed, and it was found that the electroanalytical method used can be well adopted for simultaneous electrochemical detection of AA and Azithromycin.

The United States requires labelling of food products containing major allergens, such as peanut, through the Food Allergen Labeling and Consumer Protection Act. Accurate labelling requires sensitive, specific and robust detection methods, and PCR-based techniques have proven highly effective. This article describes the transition of a previously developed multiplex real-time PCR assay for allergenic peanut to a droplet digital PCR format. The triplex droplet digital PCR assay was developed in a probe mixing format and directly compared to the established real-time PCR assay. Data are provided for thorough optimisation in the digital format, including the effects of primer and probe concentration, cycle number and annealing/extension time. Optimisation parameters influenced relative location and separation of droplet clusters but not final copy number. The droplet digital PCR assay was linear over five orders of magnitude; its lower limit of detection was 0.05 pg DNA per reaction, more sensitive than published digital PCR allergen assays. It was more precise, but not more sensitive, than the previously established real-time PCR assay. [ABSTRACT FROM AUTHOR]

A sensitive, reproducible, and cost-effective spectrofluorimetric method was developed for the quantification of solifenacin succinate in bulk and its tablet formulation. The method was validated in accordance with the International Conference on Harmonization guidelines with respect to linearity, accuracy, precision, limit of detection, limit of quantification, and robustness. Excellent linearity was noted in the concentration range of 15.0–95.0 μg/mL with a correlation coefficient (r2) of 0.9961. The limits of detection and quantitation for the proposed method were found to be 1.19 and 3.62 μg/mL, respectively. Excellent recovery of the drug was obtained from its marketed tablet formulation with the proposed method. [ABSTRACT FROM AUTHOR]

Abstract Environmental DNA (eDNA) has been increasingly utilized by academic, industry, and government groups for environmental monitoring due to its efficiency in regards to both time and cost, as well as non‐invasiveness to target organisms, and reduced dependency on trained biologists for sample collection. The methods typically employ quantitative real‐time polymerase chain reaction (qPCR) to detect the presence of a given organism's DNA in a sample. Currently, there is a drive to use qPCR data to infer biomass or abundance by quantitating the copy number or concentration of a given target gene fragment in a sample, which is often very dilute. Before eDNA can be fully accepted as an environmental decision‐making tool, however, certain aspects of the methods require standardization, including the quantification of target DNA in low copy number samples. Models that are not able to properly make use of data from highly dilute samples are severely hampered in their definitions of the limits of detection and quantification at the lower end of the detection curve. We propose a statistical model for a standard curve that relates the number of qPCR‐detected technical replicates to the copy number in the case of low copy number samples. Likelihood methods are used to estimate the parameters of the model and we derive inverse regression estimates together with their standard errors. Limits of copy number detection and quantification, and their confidence intervals are derived using a well‐accepted statistical approach thus providing a more broadly applicable and robust method for reporting eDNA abundance into the low copy number range. The method is illustrated using experimental results from multiple laboratories.

The handling of data on food contamination frequently represents a challenge because these are often left-censored, being composed of both positive and non-detected values. The latter observations are not quantified and provide only the information that they are below a laboratory-specific threshold value. Besides deterministic approaches, which simplify the treatment through the substitution of non-detected values with fixed threshold or null values, a growing interest has been shown in the application of stochastic approaches to the treatment of unquantified values. In this study, a multiple imputation procedure was applied in order to analyze contamination data on deoxynivalenol, a mycotoxin that may be present in pasta and pasta substitute products. An application of the proposed technique to censored deoxynivalenol occurrence data is presented. The results were compared to those attained using deterministic techniques (substitution methods). In this context, the stochastic approach seemed to provide a more accurate, unbiased and realistic solution to the problem of left-censored occurrence data. The complete sample of values could then be used to estimate the exposure of the general population to deoxynivalenol based on consumption data.

Copper is an important metal both in living organisms and in the industrial activity of humans, it is also a distributed water pollutant and a toxic agent capable of inducing acute and chronic health disorders. There are several fluorescent chemosensors for copper (II) determination in solutions; however, they are often difficult to synthesize and solvent-sensitive, requiring a non-aqueous medium. The present paper improves the known analytical technique for copper (II) ions, where the linear dependence between the ascorbic acid oxidation rate constant and copper (II) concentration is used. The limits of detection and quantification of the copper (II) analysis kinetic method are determined to be 82 nM and 275 nM, respectively. In addition, the selectivity of the chosen indicator reaction is shown: Cu2+ cations can be quantified in the presence of the 5–20 fold excess of Co2+, Ni2+, and Zn2+ ions. The La3+, Ce3+, and UO22+ ions also do not catalyze the ascorbic acid oxidation reaction. The effect of the concentration of the common background electrolytes is studied, the anomalous influence for chloride-containing salts is observed and discussed. [ABSTRACT FROM AUTHOR]

The generally accepted and innovative options for finding the limits of detection/determination of elements are considered concerning spectral analysis, in particular, flame atomization atomic absorption spectrometry, inductively coupled plasma atomic emission spectrometry, and inductively coupled plasma mass spectrometry. A simple method is proposed for finding the value of the lower limit of the analytical range, that is, the experimental limit of quantification (LOQexp). The proposed method's applicability and accuracy are demonstrated by analyzing aqueous solutions and solutions containing an inorganic or an organic matrix. This method can be used to assess the dynamic analytical range and identify matrix and interelement interferences. Theoretical calculations performed using the Saha ionization equation confirm the experimental data. [ABSTRACT FROM AUTHOR]

Multiple myeloma (MM) is a heterogeneous group of mature B‐cell diseases that are typically characterized by the presence and accumulation of abnormal plasma cells (PCs), which results in the excess production of monoclonal immunoglobulin and/or light chain found in the serum and/or urine. Multiparametric flow cytometry (MFC) is an indispensable tool to supplement the diagnosis, classification and monitoring of the disease due to its high patient applicability, excellent sensitivity and encouraging results from various clinical trials. In this regard, minimal or, more appropriately, measurable residual disease (MRD) negativity by MFC has been recognized as a powerful predictor of favourable long‐term outcomes. Before flow cytometry can be effectively implemented in the clinical setting for MM MRD testing, sample preparation, panel configuration, analysis and gating strategies must be optimized to ensure accurate results. This manuscript will discuss the current consensus guidelines for flow cytometric processing of samples and reporting of results for MM MRD testing. We also discuss alternative approaches to detect plasma cells in the presence of daratumumab treatment. Finally, there is a lack of information describing the subclonal distribution of myeloma cells based on their protein expression. The advent of high‐dimensional analysis may assist in following the evolution of antigen expression patterns on abnormal plasma cells in patients with relapsed/refractory disease. This in turn can help identify clonal subtypes that are more aggressive for potential informed decision. An analysis using t‐SNE to identify the emergence of PCs subclones by MFC, along with the analysis of their immunophenotypic profiles are presented as a future perspective. [ABSTRACT FROM AUTHOR]

Key issues related to determining the limit of quantification (LOQ) in practice are considered. Requirements to the value of LOQ and its precision and accuracy are formulated. It is shown that the use of a calibration curve for LOQ determination may result in erroneous conclusions for impurity determination methods. Answers to a number of questions relevant to practice are given. The precision of the LOQ value should always be checked if the LOQ is determined from a calibration curve. A typical requirement for LOQ precision is RSD ≤ 5.0%. An RSD ≤ 10% is acceptable in exceptional cases of a very low LOQ concentration. For this, the validation documentation should visually confirm the acceptability of the LOQ value by a chromatogram of a solution of the determined substance with the LOQ concentration. [ABSTRACT FROM AUTHOR]

The reliability of the measurement method in determining the mass concentration of wood dust relates to the sampling time for the detection of wood particles in the ambient air of woodworking places. The aim of this study was to calculate the mass limit of detection (LOD), limit of quantification (LOQ), and the minimal sampling time (tLOD and tLOQ) for determination and quantification of samples, based on the hardwood dust mass concentration at various woodworking places in the sawmills, floor production factories, and carpentries. Determination of the mass concentration of respirable, inhalable, and total hardwood dust from ambient air was performed using personal sampling pumps and three types of filter holders: respirable dust cyclone, Institute of Occupational Medicine IOM inhalable dust sampler, and total dust open-faced filter holder. The average limit of detection amounts to 0.052, 0.083, and 0.167 mg for respirable, inhalable, and total hardwood dust, respectively. The minimal detection sampling time for collecting all observed types of dust fractions ranged between 1.12 h and 1.72 h. The minimal quantification time for all collected hardwood dust samples ranged from 3.75 h to 5.51 h. Pearson's correlation test showed that the reliability of the measurements was affected more by the dustiness of the workspace than the real sampling time. [ABSTRACT FROM AUTHOR]

Norovirus (NoV) in oysters is a food safety risk of much concern. In order to assess the risk of the exposure, the distribution of the number of NoV copies contained in each oyster should be acquired first for comprehensively quantifying the associated risks. However, the part of the distribution below the limit of quantification cannot be obtained directly by laboratory detecting methods, which hampers accurate assessment. To tackle this challenging problem, a systematic method (Distribution Inference Method by Pooled Sampling) is proposed to infer the unobservable part of distribution based upon all measurements of the pooled samples with n = 2. Using convolutional integrals and real-coded genetic algorithm for inferring, this method has neither requirements for the type or properties of the original distribution, nor requirements for historical data, even nor requirements for the relationship between observable and unobservable parts of the distribution. A series of experiments were conducted on simulated datasets of a variety of types, including normal distribution, uniform distribution, gamma distribution, lognormal distribution, zero-inflated Poisson distribution, their combinations, and even their splicing, covering common distribution types in oyster NoV scenario and more general scenarios. The results show that almost all inferred simulation data and their original counterparts passed Kolmogorov-Smirnov tests, which implies that they are essential of the same distribution. Based on this method, a ready-to-use web system was developed for researchers to infer their original distribution with pooled-sampling measurements from the detection of NoV or even other substances., (© 2023 Society for Risk Analysis.)

Product mislabeling and/or species fraud in Traditional Chinese Medicine (TCM) not only decrease TCM quality, but also pose a potential health issue to the end user. Up to now, methods to control TCM quality have been developed to detect specific metabolites or identify the original species. However, species quantification in complex herbal formulas is rarely concerned. Here, we reported a simple Vector Control Quantitative Analysis (VCQA) method for flexible and accurate multiplex species quantification in traditional Chinese herbal formulas. We developed PCR-based strategy to quickly generate the integrated DNA fragments from multiple targeted species, which can be assembled into the quantitative vector in one round of cloning by Golden Gate ligation and Gateway recombination technique. With this method, we recruited the nuclear ribosomal DNA Internal Transcribed Spacer (ITS) region for the quantification of Ligusticum sinense “Chuanxiong,” Angelica dahurica (Hoffm.) Benth. & Hook.f. ex Franch. & Sav., Notopterygium incisum K. C. Ting ex H. T. Chang, Asarum sieboldii Miq., Saposhnikovia divaricata (Turcz.) Schischk., Nepeta cataria L., Mentha canadensis L., and Glycyrrhiza uralensis Fisch. ex DC. in ChuanXiong ChaTiao Wan, a classic Chinese herbal formula with very long historical background. We found that, firstly, VCQA method could eliminate the factors affecting such as the variations in DNA extracts when in combination with the use of universal and species-specific primers. Secondly, this method detected the limit of quantification of A. sieboldii Miq. in formula products down to 1%. Thirdly, the stability of quality of ChuanXiong ChaTiao Wan formula varies significantly among different manufacturers. In conclusion, VCQA method has the potential power and can be used as an alternative method for species quantification of complex TCM formulas.

Organic acids play a key role in central metabolic functions of organisms, are crucial for understanding regulatory processes and are ubiquitous inside the cell. Therefore, quantification of these compounds provides a valuable approach for studying dynamics of metabolic processes, in particular when the organism faces changing environmental conditions. However, the extraction and analysis of organic acids can be challenging and validated methods available in this field are limited. In this study, we developed a method for the extraction and quantification of organic acids from microbial samples based on solid-phase extraction on a strong anionic exchange cartridge and gas chromatographic-mass spectrometric analysis. Full method validation was conducted to determine quality parameters of the new method. Recoveries for 12 of the 15 aromatic and aliphatic acids were between 100 and 111% and detection limits between 3 and 272 ng/mL. The ranges for the regression coefficients and process standard deviations for these compound classes were 0.9874–0.9994 and 0.04–0.69 μg/mL, respectively. Limitations were encountered when targeting aliphatic acids with hydroxy, oxo or enol ester functions. Finally, we demonstrated the applicability of the method on cell extracts of the bacterium Escherichia coli and the dinoflagellate Prorocentrum minimum. [ABSTRACT FROM AUTHOR]

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This paper deals with the validation of a method for the determination of iron in spectrophotometric method in aqueous medium. The method is based on complex formation of iron with thioglycolic acid in alkaline medium in presence of a masking agent to produce a red purple chelate that has an absorption maximum at 535 nm wavelength. Beer-Lambert law is obeyed and linear calibration curves are obtained for the concentration range of iron from 0.1 mg/L to 30 mg/L. The reaction is found to be spontaneous in alkaline medium. The limit of detection and limit of quantification for the developed method are 0.0108 and 0.0345, respectively. Effect of different parameters like molar ratio of iron to different reagents and interferences, effect of time and effect of temperature of this method of determination have been studied. It is found that this method is moderately sensitive and has been successfully applied for the determination of iron(III) in different fields like ceramic materials, clay, sand, glass, stone, soil, water, and any inorganic iron containing compound or alloys. A comparison report is made for Chevron gas field waste material and Certified Reference Material of iron, which is done by atomic absorption and UV-visible spectroscopy techniques and found to be comparable. [ABSTRACT FROM AUTHOR]

X‐ray diffraction (XRD) analysis identifies the long‐range order (ie, the structure) of crystalline materials and the short‐range order of non‐crystalline materials. From this information we deduce lattice constants and phases, average grain size, degree of crystallinity, and crystal defects. Advanced XRD provides information about strain, texture, crystalline symmetry, and electron density. When radiation impinges upon a solid, coherent scattering of the radiation by periodically spaced atoms results in scattered beams that produce spot patterns from single crystalline samples and ring patterns from polycrystalline samples. The pattern, intensities of the diffraction maxima (peaks or lines), and their position (Bragg angle θ or interplanar spacing dhkl), correlate to a specific crystal structure. In 2016 and 2017 close to 100 000 articles mention XRD—more than any other analytical technique, and it was the top analytical technique of researchers that published in Can. J. Chem. Eng. A bibliographic analysis based on the Web of Science groups articles referring to XRD into five clusters: the largest cluster includes research on nanoparticles, thin films, and optical properties; composites, electro‐chemistry, and synthesis are topics of the second largest cluster; crystal morphology and catalysis are next; photocatalysis and solar cells comprise the fourth largest cluster; and, waste water is among the topics of the cluster with the least number of occurrences. Researchers publishing in Can. J. Chem. Eng. focus most of the XRD analyses to characterize polymers, nanocomposite materials, and catalysts. [ABSTRACT FROM AUTHOR]

STR markers have been the genetic markers of choice in forensic DNA analysis for the past twenty years, and has proven to be an extremely discriminating method for human identification in forensics. In this study, I have evaluated a six-dye STR multiplex assay composed of 23 autosomal STR loci, 1 insertion/deletion polymorphic marker on the Y chromosome, Amelogenin and two internal quality control markers (IQCS and IQCL). This Internal validation indicated that VeriFilerTM Plus PCR amplification kit was reproducible, sensitive, accurate and robust. Sensitivity testing showed that a full profile can be obtained even with 63pg of human DNA. Heterozygous allele balance varied between 99-60 % for samples with total DNA input ranging from 1 ng to 500pg. It is also suitable for mixture study. All the alleles of minor contributor were called for ratios of 1:1, 1:3 and 3:1. overall this study demonstrate that VeriFilerTM Plus PCR amplification kit is robust, reliable and suitable as an assay for human identification with forensic casework samples. [ABSTRACT FROM AUTHOR]

• A total of 86 relevant studies which quantified selenium were identified and selected. • The most used technique to quantify selenium is inductively coupled plasma mass-spectrometry. • Ways to digest selenium in complex food matrices are discussed. • Physical processes can still be applied to reduce time and optimize digestion performance. • The meta-analysis considered eight molecular formulas and analytical techniques as key groups. The intricate balance between the beneficial and harmful effects of selenium (Se) intake means that its quantification in food needs to be done correctly. Therefore, in this review, we systematized 105 articles to identify the most studied methodologies, analytical techniques, and food matrices. Among the analytical techniques employed, inductively coupled plasma mass spectrometry (ICP-MS) (n = 29) emerged as the most commonly used method. The most prevalent hydrolysis methodology to digest Se in food matrices involved the use of nitric acid combined with ultrasound, which improved both the yield and digestion time. Optimal recovery values were achieved when total Se quantification accounted for the sum of Se(IV) and Se(VI) (94.4–99.4%) and for SeCys (88–96.5%). These findings are relevant for advancing methodological approaches, and their results emphasize the importance of developing alternative, faster, and lower-cost protocols for Se quantification in foods and beverages. [ABSTRACT FROM AUTHOR]