AOAC SPIFAN Nutrients ERP Reviewer Forms (July 28, 2022)

FOR EXPERT REVIEW PANEL USE ONLY NOT FOR DISTRIBUTION

Expert Review Panel for Infant Formula and Adult Nutrition Evaluation of Method___Fluor-06______

Title: HS-GC analysis of fluoride in infant formula and adult nutritionals Author: TRISKELION Reviewer Name: Reviewer 1

Summary of Method:

A portion of sample is suspended in 3M sulfuric acid to liberate bound fluoride. Derivatization with TMCS is then completed. The TMFS derivative is then analyzed by headspace GC-FID. Method Scope/Applicability: Method notes applicability to infant formula and adult nutritional products. Validation data include precision data on several infant formula and adult nutritional NIST SRMs (NIST 1869 (IF/AN), 8260 (hydrolyzed milk IF), and 8261 (AN), 1869a (IF/AN)). SLV does not indicate the matrix used for spiking. It appears only powders were tested during SLV. General comments about the method: Method states sulfuric acid is employed to release fluoride bound to matrix. The SMPR defines fluoride as the ion or anionic salt, which indicates free fluoride. Acid treatment may liberate additional bound fluorine. Method Clarity: The method is missing several critical elements, including calibration standard preparation, system suitability, and analytical quality control. The other portions of the method are clearly written. Pros/Strengths: • Straight forward method steps. Cons/Weaknesses • Setpoints for described headspace sampler (PE Turbomatrix 40) will likely require optimization if utilizing a different headspace system vendor (Tekmar, Gerstel, etc.). Transferability between headspace samplers might be challenging. • Scope limited to powders only. Reconstitution (25g + 200 g water) is an option in the method, but it has not been validated. • Incomplete details on calibration standard prep. • System suitability and QC requirements not defined.

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