Journal of AOAC International最新文献

{"title":"Extraction and Measurement of 1,4-Dioxane in Detergents Using Headspace Microextraction Followed by Gas Chromatography.","authors":"Azizollah Nezhadali, Masoumeh Darbanian, Mohammad Reza Mohammadian","doi":"10.1093/jaoacint/qsaf027","DOIUrl":"10.1093/jaoacint/qsaf027","url":null,"abstract":"<p><strong>Background: </strong>1,4-dioxane is a hazardous by-product commonly found in sanitary detergents due to certain manufacturing processes. Accurate detection and quantification of this compound are essential for consumer safety.</p><p><strong>Objective: </strong>This study aims to develop and optimize a method for detecting and quantifying 1,4-dioxane in sanitary detergents. The approach involves electropolymerization of graphene oxide nanocomposites on stainless-steel mesh, followed by headspace microextraction (HS-ME) and analysis using gas chromatography with a flame ionization detector (GC-FID).</p><p><strong>Methods: </strong>Graphene oxide nanocomposites were electropolymerized on stainless-steel mesh to create the absorbent material. This absorbent was used in HS-ME for extracting 1,4-dioxane from sanitary detergent samples. A Plackett-Burman design (PBD) screened seven factors, including extraction time, extraction temperature, salt addition effect, stirring speed, desorption time, type of extraction solvent, and volume of extraction solvent. Based on the screening results, a central composite design (CCD) optimized the four critical factors: extraction time, extraction temperature, stirring speed, and type of extraction solvent. Quantification of 1,4-dioxane was performed using GC-FID.</p><p><strong>Results: </strong>The optimized method demonstrated a linear range of 0.5 to 200 μg/mL with a correlation coefficient (R2) of 0.9989. The limits of detection and quantification were determined as 0.15 and 0.5 μg/mL, respectively. Method accuracy, assessed through the relative recovery percentage of 1,4-dioxane, yielded values between 91.6% and 104%. Intra-laboratory reproducibility percentages ranged from 3.2 to 6.8%.</p><p><strong>Conclusions: </strong>The developed method, using electropolymerized graphene oxide nanocomposites on stainless-steel mesh for HS-ME coupled with GC-FID, provides a sensitive and accurate approach for detecting and quantifying 1,4-dioxane in sanitary detergents.</p><p><strong>Highlights: </strong>Electropolymerization of graphene oxide nanocomposites on stainless-steel mesh was successfully implemented to create an effective absorbent for HS-ME of dioxane. A systematic optimization approach, combining PBD and CCD, identified and fine-tuned critical factors influencing extraction efficiency.</p>","PeriodicalId":94064,"journal":{"name":"Journal of AOAC International","volume":" ","pages":"497-505"},"PeriodicalIF":0.0,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143672118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Ultra-High Performance Liquid Chromatography-Mass Spectrometry Method Based on Solid-Phase Extraction Developed for the Analysis of Polyphenols in Prunus Mume Sieb. et Zucc.","authors":"Weiting Wang, Xuanxuan Fan, Naidong Chen, Jingwen Hao, Manman Zhang, Zhengjun Xie","doi":"10.1093/jaoacint/qsaf028","DOIUrl":"10.1093/jaoacint/qsaf028","url":null,"abstract":"<p><strong>Background: </strong>Prunus mume Sieb. et Zucc. (P. mume) is rich in various phenolic compounds; however, there is a lack of effective quality evaluation methods.</p><p><strong>Objective: </strong>The aim of this study was to establish and validate a quality evaluation method that combines composition and activity to evaluate P. mume.</p><p><strong>Methods: </strong>Phenolic compounds were quantified using an ultra-high performance liquid chromatography-diode array detector (UPLC-DAD) and identified using quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). A solid-phase extraction (SPE) method was used for enrichment and purification. An Eclipse Plus-C18 (2.1 × 50 mm, 5 μm) column was used for separation at a flow rate of 0.25 mL/min, column temperature of 30°C, and detection wavelength of 325 nm. 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) and ferric ion-reducing antioxidant power (FRAP) assays were used to determine the antioxidant activity of P. mume. In addition, tyrosinase inhibitory activity (TIA) was verified for the first time.</p><p><strong>Results: </strong>Twelve major phenolic compounds were identified, among which taxifolin and ferulic acid were first detected in P. mume. The established UPLC-DAD method exhibited a strong linear relationship (R2 = 0.9999). The limit of detection and limit of quantitation of the standard compounds were in the ranges of 0.001-0.014 ng/g and 0.009-0.048 ng/g, respectively. The method exhibited good linearity, precision, stability, and repeatability. The phenolic compound content was in the range of 0.38-75.88 mg/g. In addition, P. mume extract showed excellent ABTS•+ radical scavenging capacity (half maximal inhibitory concentration (IC50) = 108.93 ± 9.43 μg/mL), FRAP (10.23 ± 0.11 μM), and TIA (IC50 = 4.79 ± 0.08 mg/mL).</p><p><strong>Conclusion: </strong>The established QC method based on composition and activity is dependable and can be used for QC of P. mume.</p><p><strong>Highlights: </strong>The chromatographic analysis method is reliable and can provide a reference for QC methods for the determination of ingredients and activity in flower-based foods.</p>","PeriodicalId":94064,"journal":{"name":"Journal of AOAC International","volume":" ","pages":"637-647"},"PeriodicalIF":0.0,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143694884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular Characterization, Antibiotic Resistance Pattern, and Biofilm Formation of Vibrio Parahaemolyticus Isolated from Tropical Seafood.","authors":"Ezhil Nilavan, Akshara Kumar, Visnuvinayagam Sivam, Murugadas Vaiyapuri, Reshmi Koombankallil, Toms Cheriyath Joseph, Thangaraj Raja Swaminathan","doi":"10.1093/jaoacint/qsaf037","DOIUrl":"10.1093/jaoacint/qsaf037","url":null,"abstract":"<p><strong>Background: </strong>Vibrio parahaemolyticus in seafood poses a major public health concern, particularly in tropical regions.</p><p><strong>Objective: </strong>The present study aims to isolate, assess antibiotic susceptibility, and determine the biofilm-forming ability of V. parahaemolyticus strains isolated from seafood sold in Cochin, India.</p><p><strong>Methods: </strong>One hundred seafood samples were collected from retail markets in Cochin and analyzed for V. parahaemolyticus. Phenotypic identification was confirmed through biochemical assays and molecular characterization using polymerase chain reaction (PCR) targeting toxR, tdh, and trh genes. Biofilm formation was assessed using the microtiter plate-crystal violet assay, and antibiotic resistance was determined using the disc diffusion method.</p><p><strong>Results: </strong>V. parahaemolyticus was detected in 43.0% (43/100) of the total seafood analyzed. A total of 43 isolates were confirmed by the toxR gene, of which five carried the tdh gene, while none harbored the trh gene. Antimicrobial susceptibility testing revealed 100% resistance to ampicillin, whereas all isolates were fully susceptible to chloramphenicol. The multiple antibiotic resistance (MAR) index ranged from 0.13 to 0.50. Notably, some multidrug-resistant isolates exhibited strong biofilm formation at 37°C.</p><p><strong>Conclusion: </strong>The high prevalence of antibiotic-resistant V. parahaemolyticus in seafood sold in Cochin and their ability to form biofilms underscores the need for rigorous monitoring and effective control strategies to safeguard public health.</p><p><strong>Highlights: </strong>The overall prevalence of V. parahaemolyticus in seafood from the retail market was 43.0%. The tdh gene was detected in five isolates, and none had the trh gene. All isolates exhibited resistance to ampicillin and were fully susceptible to chloramphenicol. The MAR index ranged from 0.13 to 0.50.</p>","PeriodicalId":94064,"journal":{"name":"Journal of AOAC International","volume":" ","pages":"612-619"},"PeriodicalIF":0.0,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144035725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a LC-MS/MS Method for the Determination of Lauric Arginate Ethyl Ester (E243) in Food.","authors":"Yiu-Tung Wong, Ka-Lok Chan, Odi Hang-Wah Yiu, Chun-Ching Chen, Ting-Wai Leung, Kin-Wai Yeung","doi":"10.1093/jaoacint/qsaf053","DOIUrl":"10.1093/jaoacint/qsaf053","url":null,"abstract":"<p><strong>Background: </strong>Lauric arginate ethyl ester (LAE) is a natural cationic surfactant exhibiting excellent antimicrobial activity and has been approved as a safe additive in certain food according to the Codex Alimentarius Commission (CAC) General Standard for Food Additives (GSFA).</p><p><strong>Objective: </strong>This study aimed to develop an analytical method based on liquid chromatography tandem mass spectrometry (LC-MS/MS) for the analysis of LAE in food using isotope-labeled LAE as internal standard.</p><p><strong>Method: </strong>LAE in food was extracted by a mixture of acetonitrile (ACN)-water (9:1) and analyzed by LC-MS/MS via an internal standard calibration method using LAE-d23 hydrochloride as the internal standard.</p><p><strong>Results: </strong>The limit of detection values of LAE were 0.32 mg/kg in liquid samples and 1.0 mg/kg in solid samples. The limit of quantitation values were 4.4 mg/kg and 14 mg/kg in liquid and solid samples, respectively. Spike recoveries consistently fell within the range of 90 to 110% at three different fortification levels, accompanied by a RSD below 10% in each instance.</p><p><strong>Conclusions: </strong>An analytical method with LC-MS/MS detection for the analysis of LAE in various food matrixes was successfully developed, validated, and demonstrated to be fast, robust, and reliable.</p><p><strong>Highlights: </strong>The developed analytical method with LC-MS/MS detection offered a fast and efficient way to analyze LAE in various food samples during a routine food surveillance program.</p>","PeriodicalId":94064,"journal":{"name":"Journal of AOAC International","volume":" ","pages":"558-565"},"PeriodicalIF":0.0,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144082955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dual-Gene Based Recombinase-Aided Amplification (RAA) - Lateral Flow Strip for the Sensitive On-Site Detection of Yersinia enterocolitica in Food Samples.","authors":"Tiantian Zhou, Jinlin Shen, Yu Feng, Norman F Neumann, Min Xu, Hangtian Ma, Yuhao Cao, Yuan Jiang, Yuqiu Zhang, Junxin Xue, Jian Li, Shuai Zhi","doi":"10.1093/jaoacint/qsaf038","DOIUrl":"10.1093/jaoacint/qsaf038","url":null,"abstract":"<p><strong>Background: </strong>Yersinia enterocolitica is one of the most common foodborne pathogens worldwide. Currently, most detection methods are primarily focused on pathogenic strains of Y. enterocolitica; while it has been frequently observed that traditionally believed \"non-pathogenic\" strains of Y. enterocolitica can also cause human disease.</p><p><strong>Objective: </strong>Herein, we have developed a novel dual-recombinase-aided amplification (RAA)-lateral flow test strip assay targeting both of a pathogenic marker (ail) and a conserved gene (foxA) for the rapid detection of both pathogenic and non-pathogen Y. enterocolitica strains in food samples.</p><p><strong>Methods: </strong>Primers and probes were designed and optimized for the detection of ail and foxA genes using RAA technology. The optimal RAA-LFS assay was then evaluated for specificity and sensitivity, and validated in both chicken samples spiked with a series of ten-fold diluted Y. enterocolitica cultures and 100 natural food samples including milk, chicken, beef, pork, and salmon.</p><p><strong>Results: </strong>The newly designed assay demonstrated 100% specificity and achieved a detection limit of 17 CFU/reaction for both targets, with the entire sample preparation and detection process completed within 25 min. Additionally, the assay showed high sensitivity in spiked chicken samples, achieving a detection limit of 1.03 × 10-1 CFU/mL for both targets. Validation with the natural food samples confirmed the robustness of the assay, as the results from this new assay were in agreement with those from the commonly used traditional techniques.</p><p><strong>Conclusions: </strong>In summary, the dual RAA-LFS assay integrates two genetic markers into a single test strip, providing a rapid, cost-effective, specific, and sensitive tool for on-site detection of pathogenic and common Y. enterocolitica strains.</p><p><strong>Highlights: </strong>A novel dual RAA-LFS assay for the rapid detection of both pathogenic and common Y. enterocolitica strains was developed.</p>","PeriodicalId":94064,"journal":{"name":"Journal of AOAC International","volume":" ","pages":"620-627"},"PeriodicalIF":0.0,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144059154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Discrimination of Rhizoma Paridis and its Adulterants by FT-IR and HPLC Fingerprint Combined With Chemometrics.","authors":"Lei Cheng, Jingjing Dong, Jun Qian, Yinglin Liu, Qingshu Yang, Xi Liu, Baozhong Duan","doi":"10.1093/jaoacint/qsaf052","DOIUrl":"10.1093/jaoacint/qsaf052","url":null,"abstract":"<p><strong>Background: </strong>Rhizoma Paridis (RP) is economically significant but identifies complex traditional medicine materials, which can be accidentally contaminated, deliberately substituted, or admixed with other species of similar morphological characteristics. This issue can affect quality and safety issues.</p><p><strong>Objective: </strong>In this study, the screening technique to detect adulteration in RP was developed using multiple fingerprints and chemometrics.</p><p><strong>Methods: </strong>Fourier transform infrared (FT-IR) spectroscopy and high-performance liquid chromatography (HPLC) combined with chemometrics, including similarity analysis (SA), principal component analysis (PCA), orthogonal partial least squares discriminant analysis (OPLS-DA), and hierarchical clustering analysis (HCA), were applied for the identification of RP and its adulterants.</p><p><strong>Results: </strong>HPLC analysis was more sensitive than FT-IR for differentiating RP from its contaminants. Except for the slight overlapping between Paris polyphylla var. chinensis (Franch.) Hand.-Mazz. and Paris mairei H.Lév., the remaining species could be successfully differentiated by the chemometrics method.</p><p><strong>Conclusions: </strong>This study indicates that the fingerprint of FT-IR and HPLC combined with chemometrics may be a valuable tool for discriminating RP and its adulterants.</p><p><strong>Highlights: </strong>FT-IR and HPLC combined with chemometrics analysis were developed to discriminate between RP and adulterants. The chemometrics analysis using SA and OPLS-DA indicates significant differentiation in the chemical composition of these species. This research provides important chemotaxonomic references in species identification.</p>","PeriodicalId":94064,"journal":{"name":"Journal of AOAC International","volume":" ","pages":"531-538"},"PeriodicalIF":0.0,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144113142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validation of Enzytec™ Liquid D-Glucose/D-Fructose for Enzymatic Determination of D-Glucose and D-Fructose in Selected Foods and Beverages: Official Method 2024.04 First Action.","authors":"Markus Lacorn, Thomas Hektor","doi":"10.1093/jaoacint/qsaf019","DOIUrl":"10.1093/jaoacint/qsaf019","url":null,"abstract":"<p><strong>Background: </strong>D-Glucose and D-fructose are present in honey, wine and beer, and in a range of other foodstuffs such as bread, pastries, or chocolate. Both sugars can occur as a monosaccharide or in di-, oligo-, and polysaccharides.</p><p><strong>Objective: </strong>To validate the performance of the Enzytec™ Liquid D-Glucose/D-Fructose test kit for the determination of D-glucose and D-fructose in food and beverages such as fruit and vegetable juices, soft drinks, wines, and beer.</p><p><strong>Methods: </strong>The method is based on enzymes that are part of a prepackaged kit that contains three ready-to-use components. Both sugars are phosphorylated by a hexokinase. Glucose-6-phosphate (G-6-P) and nicotinamide adenine dinucleotide (NAD) are converted to gluconate-6-phosphate and reduced nicotinamide adenine dinucleotide (NADH). NADH is measured at 340 nm. Phosphoglucose isomerase converts fructose-6-phosphate to G-6-P, which in turn is converted to gluconate-6-phosphate and NADH.</p><p><strong>Results: </strong>The test is specific to D-glucose and D-fructose and shows no side-activities or interferences with the exception of mannose and sulphite that interfere at 5.1 and 1.25 g/L or more, respectively. The measurement range is from 6.1 to 2000 mg/L for D-glucose and 5.6 to 1000 mg/L for D-fructose (100 µL test volume). Trueness was evaluated using NIST SRM 3282 (cranberry juice) and one reference wine. The recoveries ranged from 101 to 102%. Spiking of wine, beer, soft drinks, and juices resulted in recoveries between 93 and 105%. Intermediate precision is below 6% for concentrations at 25 mg/L and below 4% for higher concentrations. For automation, three applications with different test volumes and different measurement ranges were validated. Linearity is given from 5.0 to 10 000 mg/L for the sum of both sugars.</p><p><strong>Conclusion: </strong>The method is robust and accurate for manual and automated applications and was approved as an AOAC Official Method of Analysis℠.</p><p><strong>Highlights: </strong>The ready-to-use components of the test kit have a shelf life of at least 29 months.</p>","PeriodicalId":94064,"journal":{"name":"Journal of AOAC International","volume":" ","pages":"572-594"},"PeriodicalIF":0.0,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12233005/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143607671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validation of Enzytec™ Liquid L-Lactic Acid for Enzymatic Determination of L-Lactic Acid in Selected Foods and Beverages: Official Method 2024.07 First Action.","authors":"Markus Lacorn, Thomas Hektor","doi":"10.1093/jaoacint/qsaf020","DOIUrl":"10.1093/jaoacint/qsaf020","url":null,"abstract":"<p><strong>Background: </strong>Produced naturally by lactic acid bacteria, L-lactic acid is found in many fermented milk products and also in pickled vegetables, cured meats, and fish. It serves as a quality parameter in wine, beer, whole egg, whole egg powder, and juices.</p><p><strong>Objective: </strong>To validate the performance of the Enzytec™ Liquid L-Lactic acid for the determination of L-lactic acid in food and beverages such as milk and (fermented) milk products, fermented vegetable products, wines, beer, fruit and vegetable juices, egg, and egg powder.</p><p><strong>Methods: </strong>The method is based on enzymes that are part of a prepackaged kit that contains two ready-to-use components which are suitable for automation. L-lactic acids react in the presence of NAD and L-lactate dehydrogenase to pyruvate and NADH. The NADH formed is equivalent to the amount of L-lactic acid converted.</p><p><strong>Results: </strong>Ascorbic acid, 3-hydroxybutyric acid, and sulfite were found to interfere at concentrations higher than 0.2, 0.05, and 0.05 g/L in the test solution, respectively. Oxaloacetic acid and D-fructose do not interfere at concentrations at or below 0.2 and 10 g/L, respectively. The calculated LOD when using a test volume of 100 µL is 3.8 mg/L and the limit of quantitation is 10 mg/L. The practical upper measurement range is 600 mg/L. Relative intermediate precision was between 3.0 and 7.3% for pineapple juice, sauerkraut juice, wine, and liquid egg. Certified reference materials (cream cheese and wine) showed recoveries between 100 and 104%. For automation, three applications with different test volumes were validated. Linearity is given from 0.75 to 3125 mg/L.</p><p><strong>Conclusions: </strong>The method is robust and accurate for manual and automated applications. The method was approved as an AOAC Official Method of Analysis℠.</p><p><strong>Highlights: </strong>The components of the test kit have a shelf life of at least 24 months.</p>","PeriodicalId":94064,"journal":{"name":"Journal of AOAC International","volume":" ","pages":"595-611"},"PeriodicalIF":0.0,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12233004/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143607672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Highly Sensitive Determination of Tetracycline in Milk Based on Gold Nanoparticles/Graphene Oxide/Molecularly Imprinted Polymer as Recognition Element and Signal Amplifier.","authors":"Bingyuan Su, Xiaotian Tian, Kexin Zou, Wanwan Wang, Xiaomei Chen","doi":"10.1093/jaoacint/qsaf024","DOIUrl":"10.1093/jaoacint/qsaf024","url":null,"abstract":"<p><strong>Background: </strong>Tetracycline (TC) is widely utilized in aquaculture as a broad-spectrum antibiotic with notable bactericidal properties. Nevertheless, the inappropriate or excessive application of TC may result in the presence of antibiotic residues in edible tissues, presenting significant risks to human health. In this study, a TC-sensitive electrochemical sensor was developed by modifying glassy carbon electrodes with gold nanoparticles (AuNPs)/graphene oxide (GO)/TC-templated molecularly imprinted polymer (MIP) composites.</p><p><strong>Objective: </strong>A highly sensitive sensor for the detection of TC in milk.</p><p><strong>Methods: </strong>The MIP, synthesized by thermal polymerization, acted as a selective recognition element and pre-concentrating agent for TC. To improve the conductivity of the MIP film and enhance the transfer of electrons across the electrode surface, AuNPs/GO composites were embedded in the MIP film. The morphology, structure, thermal stability, and electrochemical properties of the AuNPs/GO-MIP film were characterized through the utilization of scanning electron microscopy (SEM), FTIR spectroscopy, thermogravimetric analysis (TA), and electrochemical impedance spectroscopy (EIS).</p><p><strong>Results: </strong>The modified electrode, featuring a composite film, exhibited a broad linear detection range (1-30 μg/L, 0.03-0.5 mg/L, and 0.5-20 mg/L), low detection limit (0.7 μg/L; S/N = 3), and high selectivity toward TC.</p><p><strong>Conclusios: </strong>The proposed sensor effectively quantified TC in milk.</p><p><strong>Highlights: </strong>In this study, AuNPs/GO composites were embedded to improve the conductivity of the composites; conductive MIP films were prepared and used as recognition elements and signal amplifiers. We present an electrochemical sensor for sensitive and selective detection of TC; the sensor can effectively quantify TC in milk.</p>","PeriodicalId":94064,"journal":{"name":"Journal of AOAC International","volume":" ","pages":"549-557"},"PeriodicalIF":0.0,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143672119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development and Validation of a Sensitive LC-MS/MS Method for Simultaneous Determination of Several Nitrosamines in Large Volume Parenteral.","authors":"Lukas Jost, Shiwei Zhou, Frank Sprau, Payden Trujillo, Annie Wan, Lucas Shaner, Bilig Sechin, Lars Gläser, David Young, Percy Kampeis, Weichun Yang","doi":"10.1093/jaoacint/qsaf031","DOIUrl":"10.1093/jaoacint/qsaf031","url":null,"abstract":"<p><strong>Background: </strong>Nitrosamines have gained significant attention in the pharmaceutical industry. However, due to the significant daily dosage of large volume parenteral (LVP), the detection limit for these products should be in the ng per liter range, which many published methods cannot achieve.</p><p><strong>Objective: </strong>This study aimed to develop and validate a sensitive LC-MS/MS method for the simultaneous determination of several nitrosamines in LVP drug products.</p><p><strong>Method: </strong>Nitrosamines and related internal standards were separated on a Waters ACQUITY UPLC HSS T3 (100 × 2.1 mm, 1.8 µm) column on a LC-MS/MS system with gradient elution. Prior to the LC injection, a Carbon A solid phase extraction (SPE) column was used to pretreat the test solutions. The mobile phase was composed of 0.1% formic acid in water as mobile phase A, and neat methanol as mobile phase B. Analytes were detected via multiple reaction monitoring (MRM) mode and quantitated against internal reference standards with a quantitation limit of 2.5 ng/L for N-nitrosodimethylamine (NDMA), 0.75 ng/L for other nitrosamine analytes.</p><p><strong>Results: </strong>The LC-MS/MS method was able to separate all analytes of interest by gradient elution within 15 min. The method was validated according to the guidelines described in the International Conference on Harmonization guideline ICH Q2(R2). The LOQ for NDMA is 2.5 ng/L, while for other nitrosamines, it is 0.75 ng/L in peritoneal dialysis and saline matrices. For haemofiltration solution, the LOQ is 1.0 ng/L for NDMA and 0.3 ng/L for other nitrosamines. The RSD% (n = 9) of the recovery did not exceed 25% in the method accuracy evaluation. Comparative testing in three laboratories revealed that all three laboratories are capable of accurately measuring nitrosamine levels at 10 ng/L within the intricate LVP matrix.</p><p><strong>Conclusions: </strong>The LC-MS/MS method for several nitrosamines was successfully developed, validated, and demonstrated to be accurate, robust, and specific.</p><p><strong>Highlights: </strong>The performance of this method can reach single-digit ng/L level in LVP matrices. Comparative testing was conducted in three laboratories located in China, Germany, and the United States to ensure reproducibility of the method.</p>","PeriodicalId":94064,"journal":{"name":"Journal of AOAC International","volume":" ","pages":"519-530"},"PeriodicalIF":0.0,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143782367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}