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The LMM and paired t-test had mostly the highest average power when the correlation was low and the second highest average power when the correlation was high. Type 1 error rates of these last two methods approached the nominal value of significance level when the number of test portions was moderately large (n > 20).

The LMM and paired t-test are better choices than other competing methods, and we provide an example using real data.

The LMM and paired t-test are better choices than other competing methods, and we provide an example using real data.

Niacin (NIA) is a water-soluble vitamin and the primary treatment of pellagra. No analytical method was found to assess NIA in complex mixtures with its official impurities.

Two validated, accurate, and selective chemometric models were developed to assay NIA in the presence of its four official impurities, including pyridine, a nephrotoxic and hepatotoxic substance. Additionally, the two selective chemometric models were compared by processing UV spectra in the range 220-305 nm and applying partial least squares regression (PLSR) and support vector regression (SVR) models.

A five levels five factors experimental design was chosen to exhibit a training set of 25 mixtures that had numerous variable percentages of tested substances. A test set consisting of 10 mixtures was designed to confirm the predictive power of the suggested models.

The presented results substantiate the strength of the developed multivariate calibration models to assay NIA specifically with high selectivity and accuracy (100.02 ± 1.312 and 100.04 ± 1.272 for PLSR and SVR models, respectively). The root mean square error of prediction for the validation set mixtures was applied as a main comparison tool and it was found to be 0.2016 and 0.1890 for PLSR and SVR models, respectively.

The results of the developed models and the reported HPLC method were statistically compared, where F-values and Student’s t-tests did not show significant difference in regards to accuracy and precision. The SVR model proved to be more accurate than the PLSR model, producing a high generalization capacity, while PLSR was easy to implement and fast.

PixeeMo™ is a compact instrument that enables bacterial cell counting using microfluidic chips instead of counting of colonies on culture media. Chips containing electrodes, based on fluid, electric filtering and sorting technology (FES), allow the selection of bacterial cells from other components in the sample. In the United States (US), surface water or ground water affected by surface water must be treated to reduce the total microbial load to less than 500 CFU/mL. In Japan, drinking water regulations limit the total bacterial load to 100 CFU/mL.

To validate the PixeeMoTM aerobic bacteria method based on the Japanese regulation in the range of 30-300 CFU/mL in drinking water.

PixeeMoTM aerobic bacteria method was compared to the Standard Method for the Examination of Water and Wastewater (SMEWW) 9215B (2017) using naturally contaminated drinking water.

The maximum repeatability standard deviation of the PixeeMoTM method was 14.8%. The difference of mean log10 values between the PixeeMoTM and SMEWW 9215B methods ranged from -0.015 to 0.258. Similar results were obtained in the independent laboratory study.

The PixeeMoTM method is equivalent to that of the SMEWW 9215B methods. The product consistency and stability study demonstrated no significant difference within the expiration date. The robustness study confirmed that there was no effect within the expected range. The instrument variation study also demonstrated no significant difference among the data of three PixeeMoTM instruments.

Total counts of bacteria in drinking water can be determined accurately within 1 h with PixeeMoTM.

Total counts of bacteria in drinking water can be determined accurately within 1 h with PixeeMoTM.

Turmeric is a medicinal herb containing curcuminoids, used as quality markers in dietary supplements. KI696 cell line In 2016, an AOAC First Action Official MethodSM was adopted for quantitation of curcuminoids and requires multi-laboratory reproducibility data for Final Action status.

To collect reproducibility data for the quantitation of curcuminoids in dietary supplements through the National Institutes of Health Office of Dietary Supplements/National Institute of Standards and Technology Quality Assurance Program (QAP).

Laboratories that participated in the QAP by following the Official Methods of AnalysisSM Method 2016.16, submitted data for ten turmeric products. The data were analyzed for mean, repeatability, and reproducibility standard deviations, repeatability, and reproducibility.

The initial data collection resulted in insufficient replicates (five) for each test sample to determine reproducibility, therefore laboratories were provided additional materials resulting in an incremental data approach. For hremental data multi-laboratory study. The method is suitable for quantitation of curcuminoids in most common dietary supplements.

Vancomycin, an antimicrobial, has many microbiological methods in literature, but it was not found any that follows the green chemistry principles.

The aim of this work was to develop and validate a new microbiological analytical method with a green view to determine the vancomycin potency in lyophilized powder using less quantity of diluents and culture medium, minimizing the costs and reducing the time of analysis.

The objective will be achieved using the microbiological method by turbidimetry.

Water was used as the diluent to prepare the vancomycin solution. BHI broth as used as culture media for the growth of the S. aureus ATCC 25923. The method was linear in the range of 30, 39 and 50.7 µg/mL. It was selective, with vancomycin reference and sample absorbance values very similar. The precision of the method was proved at intraday (RSD 4.42 %), interday (RSD 3.56 %) and intermediate levels (RSD 2.03%). It was accurate with mean recovery of 100.71 % and robust when changes were performed in three parameters of the method and analyzed by the F-Test and t-Test.

The method for evaluating the potency of vancomycin in pharmaceutical product was successfully developed and validated.

The method can be applied to routine quality control of vancomycin product as an alternative that contemplates the green analytical chemistry and the current pharmaceutical analyzes.

The method can be applied to routine quality control of vancomycin product as an alternative that contemplates the green analytical chemistry and the current pharmaceutical analyzes.