SPIFAN Nutrients ERP Book_9-29-15

Chlor-03 SLV FOR ERP USE ONLY DO NOT DISTRIBUTE

Linearity

To determine linearity, chloride calibration standards were injected in triplicate over seven concentration levels covering the range of 50–1000 mg/L. To establish stability of the analytical curve, three independent experiments were conducted using independently prepared standards. The calibration results show that the detection is linear over the concentration range, with a coefficient of determination >0.9999. Calibration errors at each level of the calibration curve were >5%. Check standards at the lowest point and midpoint of the analytical range were checked daily throughout the batch run. The system was recalibrated when the percent error of the check standards was >5%.

Error, % = calculated concentration – actual concentration actual concentration × 100

Accuracy

Accuracy was determined by fortifying the placebo samples (prior to sample preparation) at 50 and 100% of the typical level of Chloride found in a powdered infant formula. These recovery experiments were performed over multiple days on two different instruments. In addition, NIST SRM 1849a was analyzed during the course of this validation. Table 2 contains recovery results for Chloride on the five placebo samples respectively. The percent chloride recovered ranged from a low of 92.2% to a high of 107%. The percent relative standard deviations (RSD) ranged from a low of 0.44% to a high of 3.99%. The overall mean recovery is 99.7% with a RSD of 4.1%. With the exception of two recovery value at 92.2%, and 107%, all data meets the criteria specified in the SMPR (95-105% recovery). Results on NIST SRM 1849a can be found in Table 3 & 4. The mean value of 7707mg/Kg (n = 32), falls within the certified range of 5950-8011mg/Kg. The RSD obtained from all results is 2.05%. This is within the limits set in the SMPR.

Precision

Repeatability was evaluated on all 12 fortified AOAC SLV test material matrices including the NIST SRM 1849a using multiple instruments. Samples and standards were prepared freshly every day over six days and analyzed in triplicate to calculate the intermediate and overall reproducibility. Precision data for all samples can be found in Tables 5.

Chloride concentration ranged from 4031 to 25673 mg/Kg. Overall precision was < 6% for all samples. Percent relative standard deviations ranged from a low of 1.80% to a high of 5.58 %.

Reproducibility

Reproducibility was determined in the precision experiments conducted over multiple days and involving different lots of reagents made fresh each analysis day. In addition, two instruments were used during this validation study.