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-05 (Resubmission)

Title: Development and Validation of a Microdiffusion Potentiometric Method for the Determination of Fluorides in Infant Formula and Adult/Pediatric Nutritional Formula Author: Giampaolo Perinello and Lorenzo Papa; Mérieux NutriSciences Italia Reviewer Name: Reviewer 1 Please Provide a Brief Summary of the Resubmitted Method: Powdered samples are extracted at 60°C in a micro-diffusion cell in the presence of an acidic solution containing Hexamethydisilazane (HMDS). The released fluoride reacts with sodium hydroxide within the cell and is subsequently measured by potentiometry using a selective electrode. Liquid samples are freeze-dried before being treated in an analogous manner as the powdered samples. Was Method Scope/Applicability Updated? Yes (see highlighted text below). Previous ranges read 30 to 200 µ g/100g for liquids, 30 to 400 µ g/100g for powders. The method is applicable for the determination of free and slightly bound Fluoride in a variety of Infant Formula and Adult/Pediatric Nutritional Formula at concentrations from 3.33 to 200 μg/100g for liquids (30 to 18 00 μg/100g for powders) .

Has the resubmitted method met the requirements outlined as per the ERP recommendation/comment(s)? Summary of previous reviews and ERP recommendations: ERP Review ERP Recommendation Author Response Apr 2021 Include raw data & information including sample size on infant formula tested.

Addressed – see similar Dec 2021 recommendation Addressed – see similar Dec 2021 recommendation Somewhat addressed – see similar Mar 2022 recommendation Addressed – see similar Mar 2022 recommendation

Is method measuring total or free/weakly bound fluoride (please comment). Need information about microdiffusion cells and their specific requirements Need information about 1000 ppm stock standard used to prepare the calibrants

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