AOAC SPIFAN ERP Meeting Book-March 16, 2016

2011.06 (Fol-22) w/SLV FOR ERP USE ONLY DO NOT DISTRIBUTE

Silliker Chem, Res. Center Crete, IL – Report of A Validation of LC-MS/MS Method for Folate Analysis

The results of the analysis of folate and folate vitamers by the method are indicative of the accuracy of the method.

The Precision of the Reference material analysis: The inter-day precision of the reference material analysis of the method for folate and vitamer analysis was found to be satisfactory and in terms of % RSD ranged between 1.6 to 12.5%. The analysis of various reference materials over a period of about 3 months also provided a satisfactory accuracy and precision of the method. The Folic acid results obtained for the NIST SRM 1849a by the method over a period of about 3 months are presented in Table 25. The accuracy and interday as well as intraday precision of the method over a period of about 3 months was found to be satisfactory. Table 19: Folic Acid analysis in NIST SRM 1849a (Milk based Infant Formula) over a period of about 3 months 08/28/12 09/11/12 09/14/12 09/18/12 9/21/12 09/26/12 09/28/12 10/02/12 10/12/12 10/19/12 mcg/g Mean 2.306 2.145 2.460 2.065 2.288 2.301 2.390 2.349 2.268 2.404 %RSD 7.8% 2.9% 4.2% 1.9% 4.2% 0.4% 1.4% 5.0% 4.9% 2.3% N = 3 3 3 3 3 3 3 3 3 3 Folic Acid Results

Grand SD

Folic Acid Results Mean %RSD

10/26/12 11/02/12 11/07/12 11/13/12 11/17/12 11/26/12 11/29/12 Grand

mcg/g 2.123

2.337 1.7%

2.641 5.8%

2.170 3.5%

2.147 6.2%

2.241 0.5%

2.277 5.5%

2.282

0.151

2.4%

6.6

N =

3

2

3

3

3

3

3

50

50

NIST Value

2.293 + 0.062

Micro Results

2.31* *Result for total folate in sample as folic acid (based on a single analysis)

5-methyl-THFresults obtained for the NIST SRM 1849a by the method over a period of about 3 months are presented in Table 26. The comparison of the results obtained vs NIST specified value has already been discussed earlier. The NIST values reported are about half of obtained by the method. Reliability of the NIST values is in doubt as those are based on NIST in house method and not confirmed by any other lab and likely the methodology used may be older and may lack some features like use of internal std. as the compounds were not available till recently. Interday as well as intraday precision of the method over a period of about 3 months was found to be satisfactory.

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