Journal of AOAC International最新文献

Background: Analytical validation is a sequence of operations aiming to evaluate the accuracy, reliability, and cost of analytical results for making informed decisions in method selection and meeting the requirements of regulatory institutions.

Objective: This study aims to perform an analytical validation by comparing three different approaches: the accuracy profile, the uncertainty profile, and the conventional validation to assess the capability of each method in confirming the robustness of the results.

Methods: The accuracy profile offers a comprehensive assessment of analytical performance and integrates systematic and random errors to determine if future results will satisfy the predefined acceptance limits. Meanwhile, the uncertainty profile, which is complementary and innovative, allows the uncertainty estimation from validation data. These approaches were developed after conventional validation that relies on statistical methodologies based on separate evaluations of method criteria to provide a comparative framework for evaluating new methods.

Results: This comparison will give recommendations for best practices related to analytical validation. The uncertainty profile is a graphical decision-making tool for determining full validation by integrating analytical validation and the estimation of measurement uncertainty, evaluating two statistical methods: β-expectation tolerance intervals and β-content, γ-confidence tolerance intervals, using a formula introduced by Saffaj δ Ihssane, predicting that 95% of future results will fall within the acceptance limits of ± 5%, revealing that the tolerance intervals for β-expectation are smaller than β-content, γ-confidence.

Conclusion: The total error approaches offer robust recommendations for optimal methods for routine application.

Highlights: This study highlights the critical need for appropriate analytical validation and the challenges arising from the absence of clear guidelines for that purpose. Different approaches emphasize the significant impact of the choice of an adequate method, which remains pivotal for providing accurate results under real-world scenarios. Concrete examples and simulations illustrate the viewpoints associated with different approaches to making decisions.

Background: Per- and polyfluoroalkyl substances (PFAS) comprise thousands of fluorinated chemicals. They are of growing concern because many PFAS compounds are persistent and toxic. Food contact materials (FCM) containing PFAS pose multiple exposure pathways to humans, prompting twelve states to enact laws banning FCM with PFAS levels exceeding 100 ppm of TOF.

Objective: While LC-MS is often used to measure targeted PFAS compounds, much of the total PFAS content in the sample may be missed. To understand organic fluorine content in samples more comprehensively, we developed a method using combustion ion chromatography (CIC) to measure TOF and extractable organic fluorine (EOF) in FCM.

Method: This technology utilizes combustion under an oxygen and argon atmosphere. All gaseous, acidic combustion products are collected in water, with ions separated on an ion exchange column and detected by conductivity. Total fluorine (TF) was measured by combusting 10-50 mg of FCM. Total inorganic fluorine (TIF) was measured by extracting cryo-ground FCM with water followed by direct injection to the IC system. TOF was then calculated by subtracting TIF from TF. EOF was determined by CIC after extracting analytes from the ground FCM using 80% methanol/20% acetonitrile.

Results: The Method detection limit (MDL) for TOF is 0.51 ppm, exceeding the sensitivity requirements of current state regulations. A comparison of EOF to TOF revealed that EOF constitutes less than 15% of the TOF in the FCM samples.

Conclusions: TOF is a critical metric for assessing PFAS contamination in FCM, as targeted LC-MS approaches may miss much of the PFAS in the samples.

Highlights: We developed a sensitive and automated method to determine TOF and EOF in FCM. The method can be used to screen for PFAS in FCM, ensuring compliance with current regulations on PFAS contamination.

Background: Yogurt has emerged as an essential nutritional food in contemporary diets, and the development of new multi-component yogurt formulations has become a focal point of current research.

Objective: In this study, the effects of fermentation compounds and the addition of sugar, soy milk on the quality and probiotic activity of milk-soy mixed yogurt were studied to determine the optimal formation of mixed yogurt.

Methods: The various fermentation compounds (YO-MIX 883, Lactobacillus Casei complex starter cultures, Lactobacillus Paracasei compound starter cultures), different concentrations of milk-soy additions (0, 25, 50, 75, 100%) and sugar (2, 4, 6, 8%) were tested within each experimental group, and the pH, appropriate acidity, and total viable bacterial count of the fermented milk-soy mixed yogurt were determined throughout the fermentation and refrigeration processes.

Results: The obtained results showed that the Lactobacillus Paracasei complex was particularly effective for the fermentation of soy milk. The mixed yogurt formulation, comprising 50% soy milk and 4∼6% sucrose, exhibited enhanced acidity, superior sensory evaluation scores, and overall improved product quality. It was observed that during refrigeration, an increase in the milk content of yogurt corresponded to a more pronounced post-acidification effect. The optimal formulation for the milk-soy mixed yogurt identified in this research consisted of 0.3% Lactobacillus Paracasei compound fermenter, 6% sucrose, and 40% soy milk. Under these optimal conditions, the mixed yogurt achieved an acidity level of 76°T, a sensory score of 92 points, and a survival rate index of 1.25. Additionally, the yogurt exhibited a distinctive soybean aroma in its aftertaste, contributing to its overall quality. Furthermore, the probiotic survival index of the mixed yogurt containing 40% soy milk, following simulated gastrointestinal fluid digestion, was recorded at 0.767, indicating that the probiotic activity in this yogurt was significantly higher than that of other yogurts.

Conclusion: The obtained results provide a theoretical foundation for the future industrial production of milk-soy mixed yogurt products.

Background: The 2018 Farm Bill defines hemp as Cannabis sativa L. with a tetrahydrocannabinol (THC) concentration not more than 0.3% on a dry weight basis where THC is implied to be total THC (THCTotal) including both acid (Δ9-THCA) and neutral (Δ9-THC) forms.

Objective: Effect of temperature and mass were studied to determine the quickest time to prepare fresh hemp suitable for grinding without affecting THCTotal. Proficiency testing program data were also analyzed to compare THCTotal contents on a dry versus wet weight basis.

Methods: Fresh hemp of 150 and 400 g were freeze-dried or heat-treated at 50°C, 60°C, and 70°C for various lengths of time up to 72 h. Ground hemp was analyzed for moisture content via AOAC 934.01 and THCTotal via liquid chromatography/mass spectrometer (LC/MS) or gas chromatography with flame ionization detection (GC/FID). A data set analyzed from a proficiency testing program included moisture and THCTotal from 20 to 67 laboratories on 12 analytical samples circulated from 2020 through 2022.

Results: The quickest drying time of 24 h occurred at 70°C with 150 g. These conditions did not affect THCTotal content on a dry weight basis. Twelve proficiency testing program analytical samples ranged from 5.8% to 11.4% moisture and 0.144% to 0.399% THCTotal on a wet weight basis. An increase in reported THCTotal on a dry weight basis compared to a wet weight basis ranged from 0.002% to 0.027% with a significant difference occurring in only one analytical sample.

Conclusions: Suitable conditions for drying hemp without altering THCTotal content were 24 h at 70°C. Determining residual moisture in oven-dried ground hemp to calculate THCTotal content on a dry weight basis provides no benefit given the minimal difference between contents on dry versus wet weight bases, interlaboratory variability, and terpene volatilization.

Background: Premna microphylla Turcz. (PMT) is a traditional food and medicinal plant, which has been used to treat cure hemostasis, rheumatism, and dysentery. However, there is still a lack of a clear understanding of the chemical profile of PMT and its metabolites in vivo.

Objective: To establish a rapid and efficient analytical method for the identification of phytochemicals in PMT and their metabolites in vivo.

Methods: First, the fingerprint of PMT was established by HPLC with method validation. Then, the phytochemical composition of PMT leaves was identified using ultra-performance liquid chromatography-quadrupole time-of-flight-tandem mass spectrometry (UPLC-QTOF-MS/MS). Finally, the prototype and correlated metabolites were detected after oral administration in mice to understand the absorption and metabolism of phytochemicals in vivo.

Results: The results showed that the established HPLC method for fingerprint evaluation of PMT has good precision, repeatability, and stability. Additionally, a total of 103 phytochemicals were identified in PMT, including mainly flavonoids and terpenoids. Then, 37 prototype components and 20 derived metabolites in vivo were detected.

Conclusion: In this study, we constructed a fingerprint method, which has good stability, precision, and repeatability, and the fingerprint of PMT was established. Then, the chemical profile of PMT in vitro and in vivo was determined. The results showed that flavonoids and terpenoids were the main phytochemicals in PMT, and methylation, sulfonation, and dihydroxylation were the main metabolic pathway in vivo.

Highlights: The present study provides the phytochemical basis for subsequent study of pharmacological activity.

Background: The leaves of Elaeagnus angustifolia, belonging to the Elaeagnaceae Juss. family, are known for their medicinal properties for relieving cough and asthma, as well as treating dysentery and diarrhea.

Objective: To establish a rapid qualitative method for the detection of secondary metabolites in leaves of Elaeagnus angustifolia, including the identification and analysis of various secondary metabolites in leaves of Elaeagnus angustifolia.

Method: Samples were separated using a Waters ACQUITY H-Class ultra-performance liquid chromatography (UPLC) system (FTN autosampler, quaternary LC pump) and ACQUITY UPLC® BEH C18 column (1.7 μm, 2.1 mm × 100 mm). The flow rate was set to 0.4 mL/min, the injection volume was 1.0 μL, and the column temperature was set to 45°C. The mobile phase was methanol (A) with -0.1% formic acid in water (B). Samples were analyzed by quadrupole time-of-flight mass spectrometry (Q-TOF-MS).

Results: A total of 182 different secondary metabolites were detected from 10 varieties of leaves of Elaeagnus angustifolia, including 77 flavonoids, 20 steroids, 7 alkaloids, 15 amino acids, 18 organic acids, and 45 other compound types.

Conclusions: A method for the rapid analysis of leaves of Elaeagnus angustifolia by UPLC-Q-TOF-MS was established, and the secondary metabolites in leaves of Elaeagnus angustifolia were identified. The enrichment of secondary metabolites in leaves of different varieties of Elaeagnus angustifolia was clarified.

Highlights: The UPLC-Q-TOF-MS method is very fast and possesses a high degree of selectivity, precision, and sensitivity. These findings provide a reliable foundation for the development of medicinal resources derived from Elaeagnus angustifolia leaves.

Background: Hemodialysis solutions are liquid concentrates used during hemodialysis sessions. They are commonly used as a renal replacement therapy.

Objective: This study aimed to develop a method to determine Na, K, Ca, and Mg in hemodialysis solutions by high-resolution continuum source flame atomic absorption spectrometry (HR-CS F AAS) using Design of Experiments (DOE).

Methods: The combination of the Doehlert Matrix with the desirability function was used to establish a compromise condition in the optimization of the significant variables studied: 60 L/h for acetylene flow rate, 8 mm for burner height, and 0.25% (w/v) and 0.60% (w/v) for Cs and La concentrations. The method was validated by following the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines and parameters, and, as such, the selectivity, linearity, precision, accuracy, and robustness were evaluated.

Results: Calibration curves with the ranges of 25-130 mg/L for Na, 1.0-5.0 mg/L for K and Ca, and 0.30-0.70 mg/L for Mg were employed. The method proved to be precise (RSD lower than 2.7%) and accurate (mean recovery data, contemplating the three levels added, were 103.0% for Na, 100.5% for K, 101.3% for Ca, and 101.5% for Mg).

Conclusions: The developed method enables the sequential multielement determination of Na, K, Ca, and Mg in a single run. Requiring only one dilution step, this method significantly reduces analysis time for both sample and standard solution preparation and measurement.

Highlights: This study presents the first method reported in the literature for multielement determination in hemodialysis solutions, offering an alternative approach to the current European Pharmacopeia method.

Background: Burkholderia gladioli pv. cocovenenans is a notable foodborne pathogen that poses a significant risk to food safety. Contaminated food requires distinct classification and treatment procedures for non-pathogenic B. gladioli and its pathogenic subspecies cocovenenans. Hence, establishing a rapid and sensitive detection method to distinguish them is necessary.

Objective: In this study, we aimed to establish a method combining the CRISPR-Cas12a/Cas13a (Clustered regularly short palindromic repeats-CRISPR associated proteins 12a and 13a) dual system with recombinase-aided amplification for rapid, specific, and sensitive detection of non-pathogenic B. gladioli and pathogenic subspecies cocovenenans in food.

Methods: First, an RAA (Recombinase-aided amplification)-CRISPR-Cas12a/Cas13a method was developed, and its feasibility was assessed. Next, specificity was analyzed using 23 strains of B. gladioli and 5 non-target strains. Following this, sensitivity was evaluated by preparing gradient dilutions of B. gladioli pv. cocovenenans bacterial solutions. Finally, real food test samples, including fresh noodles and tremella artificially contaminated with B. gladioli pv. cocovenenans, were utilized for method validation and sensitivity comparison.

Results: The established RAA-CRISPR-Cas12a/Cas13a method exhibited high specificity and achieved 100% accuracy in detecting species B. gladioli and its subspecies cocovenenans. This rapid method could be finished within 45 min with a detection limit of 100 CFU/mL (Colony-forming units per millilter) for bacterial concentration. Additionally, it achieved detection limits of 102 CFU/g for fresh noodles and 103 CFU/g for tremella.

Conclusion: The rapid RAA-CRISPR-Cas12a/Cas13a method demonstrated high specificity and sensitivity in detecting and distinguishing species B. gladioli and subspecies cocovenenans in both food test samples and post-cultivation colonies.

Highlights: The RAA-CRISPR-Cas12a/Cas13a method presented in this study offers a novel molecular approach for the rapid, accurate, and sensitive detection of B. gladioli and its subspecies cocovenenans in foods.

Background: Acesulfame K (E950) and saccharin Na (E954) are commonly utilized synthetic sweeteners that are added to various processed food products to improve the sweet flavor. Environmentally friendly technology must be prioritized when evaluating the artificial sweeteners, as excessive consumption of these sweeteners presents serious health hazards.

Objective: The main aim of this study was to develop an analytical quality by design-aided eco-friendly RP-HPLC technique that can detect both acesulfame K and saccharin Na simultaneously, incorporating green analytical chemistry (GAC) principles and white analytical chemistry (WAC), using the ultrasound-assisted extraction (UAE) technique on commercial food samples.

Methods: The usage of ethanol was in accordance with eco-friendly ideals due to its ease of use, speed, and lack of environmental impact. Rotatable central composite design (rCCD) was used for method optimization. A mobile phase consisting of an ethanol-1% aqueous acetic acid (1 + 1, by volume) mixture was used and the separation was carried out on a Zorbax column (SB-C18, 150 × 4.6 mm, 5 µm) at a flow rate of 1 mL/min and a detection wavelength of 217 nm.

Results: Acesulfame K had a retention time of 1.134 min and saccharin Na of 2.134 min. Acesulfame K and saccharin Na recovery rates varied betweeen different commercially available food samples, ranging from 65 to 102% and 75 to 101%, respectively.

Conclusion: At the defined operating point, the developed procedure displays conformity with the previously defined requirements for linearity, accuracy, sensitivity, and repeatability. The most accurate assessments of greenness were produced by the Green Analytical Procedure Index (GAPI), Analytical Eco Scale (AES), and Analytical GREEnness metrics (AGREE) tools. Results from the Red-Green-Blue 12 (RGB 12) algorithm for whiteness and Blue Applicability Grade Index (BAGI) for blueness indicate that the method is very practical, cost-effective, and environmentally friendly.

Highlights: The results of this study could pave the way for more eco-friendly and effective AQbD methods to be used in the future for evaluating various sweeteners using green solvents.