Journal of AOAC International最新文献

Background: Azithromycin is a complex molecule derived from erythromycin. The control of its dosage in conventional release tablets requires the analytical validation of its method to ensure accurate quantification and provide confidence in the reliability of the results for informed decision-making.

Objective: This study aims to validate an innovative method for azithromycin quantification using the accuracy profile. Additionally, a comparison is made between the uncertainty measurements calculated from the validation data using two formulas proposed by Feinberg et al. and Saffaj and Ihssane and contrasted with the ISO GUM approach.

Methods: A liquid chromatography system intended for azithromycin analysis equipped with a reversed-phase C18 stationary phase consisting of octadecyl silyl vinyl polymer in a UV detector operating at 210 nm at a temperature of 40°C in isocratic elution using a mobile phase of acetonitrile and dipotassium hydrogen phosphate buffer (6.7 g/L), in the fraction of (60:40, v/v) at pH = 8.

Results: The various accuracy profiles are illustrated to ensure that a known quantity of anticipated findings acquired through the method stand inside the tolerance interval of 95% and remain within the previously set acceptance limits of ±5%. Measurement uncertainty provides comparable values using both formulas of the total error approach. However, it was observed that the ISO-GUM approach tends to overestimate the expanded uncertainty. Specifically, while the ISO-GUM approach provides a rigorous framework, the use of the validation data offers a more empirical uncertainty estimation.

Conclusion: The approach based on the total error grants the ability to accurately close the routine uncertainty, emphasizing a complete validation.

Highlights: The proposed method is robust for pharmaceutical application, demonstrating good accuracy, with 95% of tolerance and uncertainty limits falling within the predefined acceptance limits of ±5%.

Background: Ochratoxin A (OTA) is a mycotoxin produced by multiple fungal species and is found in a variety of foods. Ingestion of OTA-contaminated foods by lactating mothers can lead to OTA exposure in infants.

Methods: To help assess infants' exposure to OTA, milk samples from the Maternal-Infant Research on Environmental Chemicals (MIREC) Human Milk Study were analyzed. Human milk samples were collected (n = 494) and analyzed for OTA levels by HPLC.

Results and discussion: The mean OTA concentration was 7.32 ± 9.25 ng/L, with 390 (79%) test samples testing positive for OTA and a range of 4.5-192 ng/L. Based on the food consumption questionnaires distributed among participants, higher OTA levels were observed with higher consumption of cottage cheese, hot cereal, and whole-grain bread and significant differences were found in OTA levels at different sites. The mean OTA level in the analyzed milk test samples was well below the amount found in infant formulas sold in Canada, which was determined by Health Canada to be safe.

Conclusions: The concentrations of OTA found in human milk in this study are well below the amount deemed safe in infant formula by Health Canada and, therefore, unlikely to be of concern to infant health.

Background: As a new cosmetic ingredient, NMN is widely used in cosmetics production, but due to the lack of a detection method, QC of related products cannot be achieved.

Objective: This study will develop a detection method for NMN in three matrixes (facial mask essence, emulsion, and cream) for QC of related cosmetics.

Methods: Given the high ester content in facial emulsions and creams, which can hinder the detection of trace substances, a novel multi-plug filtration clean-up (m-PFC) purification column packed with multi-walled carbon nanotubes (MWCNTs) was employed to purify these matrixes. An HPLC method for NMN in three matrixes (facial mask essence, emulsion, and cream) was established. Methodological verification was conducted.

Results: Results demonstrated a good linear relationship within a range of 5.0-500 μg/mL, with an LOQ of 5.0 mg/kg. The RSD of the precision experiment was less than 3%, and the RSD for six repeated experiments ranged from 1.2 to 5.3%, indicating the method's stability, reliability, and good repeatability. Recovery rates in the three cosmetic matrixes were between 93.9 and 109.4%, with an RSD below 3.7%. This method was applied to detect NMN content in seven cosmetics purchased from an e-commerce platform; NMN was not detected in some products claiming to contain NMN.

Conclusion: This method had the advantages of simple operation, high sensitivity, and good accuracy, and provides technical support for cosmetic regulation.

Highlights: Through this study, we should raise awareness and supervision of NMN cosmetics by establishing relevant standards.

Background: An accurate determination of fiber concentrations in feeds and feces is critical for the measurement of fiber digestibility in pigs. The method of AOAC INTERNATIONAL for determining amylase-treated neutral detergent fiber (aNDF; Method 2002.04) has been widely used for pig diets. To overcome the complexity of the AOAC procedure, the Ankom method is also available for determining aNDF. Although these two methods have been compared for ruminant diets and feces, a comparison of the methods for pig diets and feces has not been documented.

Objective: The objective was to compare aNDF values determined by the AOAC (aNDFAOAC) and the Ankom methods (aNDFAnkom) of ingredients, diets, and feces for pigs.

Methods: A total of 255 test samples, consisting of 26 feed ingredients, 39 diets, and 190 feces of pigs, were analyzed for aNDF. To compare the AOAC Method 2002.04 and Ankom methods for aNDF, regression analyses were performed with the aNDFAnkom minus the mean aNDFAnkom as an independent variable and the aNDFAOAC minus the aNDFAnkom as a dependent variable.

Results: The aNDFAnkom were greater than the aNDFAOAC by 2.90% (standard error = 0.63; P < 0.001) on average for ingredients and by 2.56% (standard error = 0.34; P < 0.001) on average for diets. For feces, the aNDFAnkom were greater than the aNDFAOAC by 1.30% (standard error = 0.32; P < 0.001) on average. The differences between the aNDFAnkom and aNDFAOAC were not consistent across the data ranges represented by a linear bias (slope = -0.16; standard error = 0.04; P < 0.001) in feces.

Conclusion: ANDF concentrations determined by the Ankom method were greater than from the AOAC method in pig feeds and feces.

Highlights: Despite convenience, the Ankom method yields greater aNDF values compared with the AOAC method.

Cranberry fruit samples of 15 genotypes (cultivars and accessions) grown in 16 locations in 4 states (MA, NJ, OR, and WI) and a Canadian province (British Columbia) were analyzed by non-targeted fuzzy chromatography-direct injection mass spectrometry (FC-DIMS). The data collected for 206 ions were analyzed by multifactorial multivariate analysis of variance-principal component analysis (MFMV-ANOVA-PCA). MFMV-ANOVA-PCA showed that sample composition varied statistically (p < 0.001) with respect to the major factors (state/province, growing location, genotype, and analytical batch) and cross factors (genotype-state/province and genotype-growing location). MFMV-ANOVA-PCA score plots verified a systematic variation with respect to 42 genotype-state/province pairs and 82 genotype-growing location pairs. MFMV-ANOVA-PCA variable loadings identified major ions that varied with each of the major factors and cross factors and 56 ions were annotated. The location-ion count matrix was transposed and analyzed by hierarchical cluster analysis producing dendrograms that grouped ions with respect to metabolic pathways for either the genotype-state/province or genotype-growing location pairs. Annotation of the ions in the hierarchical clusters allowed evaluation of the impact of genetics and location on compounds of interest. Ions expected to correlate with fruit quality measurements (brix, titratable acid, total anthocyanins, and total proanthocyanidins) were identified. This study demonstrates that mass spectral data coupled with chemometric analysis is a valuable tool for predicting the composition of specific genotypes for specific growing locations. The general design of this study can be used as a model for other food plants.

Background: Poppy Active Pharmaceutical Ingredients (APIs) are mainly used in the production of antitussives, analgesics, and other preparations. The alkaloid components play a major role, but the use of some alkaloids can cause dependence and toxic side effects in patients.

Objective: The main aim of this study was to develop an effective and simple high-performance liquid chromatography (HPLC) for the simultaneous determination of five alkaloids in three APIs.

Method: Waters XBridge C18 column (4.6 mm × 150 mm, 3.5 μm) was used as the chromatographic column. Mobile phase A was composed of 5.5 mmol/L sodium heptane sulfonate solution-acetonitrile-methanol-phosphoric acid (83:7:10:0.22, v/v/v/v), and Mobile phase B was composed of 5.5 mmol/L sodium heptane sulfonate solution-acetonitrile-methanol-phosphoric acid (60:15:25:0.45, v/v/v/v). The flow rate was 1.2 mL/min; The detection wavelength was 230 nm; The column temperature was 40 °C.

Results: The HPLC method was suitable for the simultaneous determination of the contents of five alkaloids in three APIs. The verification experiment showed that the linear relationship of the five alkaloids in their respective ranges was good (R2 ≥ 0.998); The average recoveries ranged from 87.62 to 103.18%; The RSDs of repeatabilities were 0.3∼2.7%.

Conclusions: In this study, a new HPLC method was developed and successfully validated. Compared with the determination method of opium alkaloids specified in Pharmacopoeia, this HPLC method does not need a complex sample pretreatment process, improves detection efficiency, avoids the use of highly corrosive reagents, and reduces the experimental risk. It can simultaneously meet the determination of five alkaloids in three APIs.

Highlights: This method can simultaneously quantify five alkaloids in three poppy APIs without a complex sample pretreatment process and the application of strong corrosive solvents. It is applied to these APIs for the first time, expanding the scope of alkaloid analysis and providing new data for comparative studies of different API sources.

Background: Salmonella, a notorious foodborne pathogen with a wide range of hosts, poses a significant public health concern globally. Contaminated surface water acts as a potential source of Salmonella transmission.

Objective: To optimize a Salmonella detection method from large-volume water and analyze surface water samples in Beijing and characterize Salmonella isolates from these samples by whole genome sequencing.

Methods: A microbial enrichment device based on the modified Moore swab (MMS) design was optimized and validated. Thirty-five water samples were collected and analyzed for Salmonella from 11 park lakes, two rivers, and two farms. Multiple characteristics of isolates were analyzed using antibiotic antimicrobial testing and whole genome sequencing.

Results: The optimized MMS unit showed high efficiency (over 80% recovery) and a low detection limit (100 cells) for enriching and isolating Salmonella from large-volume water (10 L). Compared to the conventional method, the MMS device significantly improved Salmonella detection efficiency (62.86 versus 8.57%) in Beijing's surface water. Most of the Salmonella isolates from surface water belonged to rare serotypes from water wildlife susceptible to all the tested antimicrbials.

Conclusion: The study demonstrates the optimized MMS's effectiveness for on-site enrichment of pathogens from large-volume water, validates the accuracy and sensitivity of a Salmonella detection method for surface water, and reveals previously unknown information about Salmonella contamination in Beijing's public water system.

Highlights: Salmonella concentrations in water are typically very low: implementation of this method would successfully realize large-volume water sampling and on-site pathogen enrichment, and significantly improve Salmonella detection efficiency in surface water.

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 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 and 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 in real-world scenarios. Concrete examples and simulations illustrate the viewpoints associated with different approaches to making decisions.

Background: Moxidectin is an active pharmaceutical ingredient (API) extensively used in various drug products within the pharmaceutical and animal health sectors. Despite its widespread use, the analytical methods prescribed by the United States Pharmacopeia (USP) and European Pharmacopoeia (EP, Ph. Eur.) exhibit significant limitations. These methods fail to adequately separate key impurities of (23Z)-moxidectin (EP impurity L) and 3,4-epoxy-moxidectin, potentially affecting the quality control, purity assessment, and safety of moxidectin-containing products.

Objective: The objective was to develop and validate an alternative, improved stability-indicating high-performance liquid chromatography (HPLC) method for the identification, assay, and quantification of related substances in the moxidectin drug substance, along with the analysis of its degradation pathways.

Methods: High-resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR) were employed to comprehensively examine moxidectin and its two degradation products under specified acidic conditions. The degradation products were isolated and identified using a range of analytical techniques, including HRMS, NMR, and other relevant methods.

Results: The epoxy derivative of moxidectin (relative retention time [RRT] = 1.2) was not identified under the studied acidic degradation conditions. HRMS data indicated that the degradant at RRT = 1.2 is an isomer of moxidectin, as it exhibited an identical molecular ion. Detailed NMR studies on moxidectin and its impurity at RRT-1.2 revealed differences in carbon and proton chemical shifts at positions C-22 and C-24, strongly supporting the identification of the structure as an oxime geometric isomer of moxidectin, i.e. (23Z)-moxidectin.

Conclusions: The findings revealed specific degradation products formed under acidic conditions, offering valuable insights into the chemical transformations of moxidectin. This information is crucial for assessing the drug's stability profile and ensuring the quality and safety of moxidectin-containing products.

Highlights: The HPLC method developed in this study significantly improves on existing USP/EP methods with regard to a separation of key impurities of (23Z)-moxidectin and 3,4-epoxy-moxidectin, offering robust performance for routine analysis of bulk moxidectin API batches and stability samples in quality control (QC) laboratories.