SPSFAM ERP

D. Analytical Range and Linearity Range was established by evaluating the linearity, precision, and accuracy of data at the extreme ends of the calibration curve. Samples between 0.1% to 67% of an individual analyte were included in the validation. Based on the calibration range, the typical sample weight, and possible dilutions the range of the method is between 0.1% and 75% of an individual analyte. To insure complete solubilization of the analytes the least soluble compound, lactose, was dissolved at the typical sample weight and extraction volume (2.5 g into 500 mL of extraction solution). Lactose completely dissolved, which demonstrates the extraction solution is effective in solubilizing the analytes of interest. The linearity, accuracy, and precision results for the matrices included in this multi-lab validation are discussed in the Results and Discussion sections D, F, and G, respectively. The validated analytical range of the method covered the required range of AOAC SMPR 2018.001 [1] . The linearity was evaluated by analyzing three separate days of calibration curves from each validation site at 0.5 µg/mL, 2 µg/mL, 5 µg/mL, 10 µg/mL, and 15 µg/mL. Calibration curves from the Breakfast Cereal NIST 3233 SRM sequences were used to demonstrate acceptable linearity. The calibration was performed using arabinose internal standard and the data was fit to a 1/x weighting and a linear regression model. Acceptable linearity was demonstrated by coefficients of determination (r 2 ) of ≥ 0.998 and a standard point residual percent deviation ≤10 % for the lowest calibration level and ≤5% for all other calibration levels. These calibration criteria are identical to the method system suitability criteria, therefore all validation data met these linearity criteria. The statistical data from the calibration curve residuals and r 2 from different analysis dates are summarized in Appendix I Tables AI-4-1 to AI-4-7 . The coefficients of determination (r 2 ) were all >0.998 and the individual point residual percent deviation met the specified criteria for all analytes, demonstrating an acceptable linearity across the calibration range.