AOAC SPIFAN Nutrients ERP Method Reviews (September 7, 2019)

FOR EXPERT REVIEW PANEL USE ONLY NOT FOR DISTRIBUTION

Precision (RSD r ): SMPR: for all analytes in mg/100g

0.4 – 5.0 ≤ 4% 5.0 – 50 ≤ 3% 50 – 2500 ≤ 2%

1- Method for determination of total proteinogenic amino acids and taurine

Repeatability was determined in 17 different matrices in duplicate on each of the 6 days by two different analysts. The RSDr was calculated on all the 12 data points (6 sets) on all the 17 SLV matrices. The highest mean RSDr of all matrices was observed for CYSx and was not more than 2.7% and is well below the lowest set limit of 3% as per SMPR.

2- Method for determination of free aminoacids

Repeatability was determined by analysing the laboratory recovery samples prepared for accuracy validation. The %RSD was calculated on each levels and the mean RSDr of all the three levels for all the free amino acids were below the lowest set limit of 3% as per SMPR. The system precision of the analytical procedure was determined using six replicate injections of a mixed working standard which consists of all the target amino acids. The relative standard deviation of area ratio and retention time was found to be not more than 1%.

Intermediate Reproducibility (RSD iR ):

1-Method for determination of total proteinogenic amino acids and taurine

Intermediate reproducibility (within laboratory reproducibility) was calculates from the six sets of duplicares of 17 different matrices using one way Analysis of Variance (ANOVA). The highest mean RSD iR for all matrices was observed for taurine (0.48) and is bellow the set limit of 5% on SMPR.

• System suitability: The system precision of the analytical procedure was determined using 6 replicate injections of a mixed working standard which consists of all the target amino acids. The relative standard deviation of area ratio and retention time was found to be not more than 1%.

Recommendation:

I recommend move the method to first action.

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