AOAC SPIFAN Nutrients ERP Method Reviews (September 7, 2019)

FOR EXPERT REVIEW PANEL USE ONLY NOT FOR DISTRIBUTION

if blanks are injected with every set of check standards or only with first – should be clarified in final method document. 4 check standards of fluoride in water (5, 10, 160, 500 mcg/kg) are injected in duplicate between calibrants and samples, and should be repeated every 12 h and at the end of each analytical batch. During validation, recoveries of check standards were 99-113% with RSDs of recoveries between replicates of the same check standard were 4-9% Check standards are also used to confirm stability of the dialysis transfer time ( ± 5 s). Fluoride retention time should be 7.5 ± 0.7 min. Recommendation: This method demonstrated performance that meets SMPR 2014.016 for fluoride in infant and adult/pediatric nutritional formulas. While I have reservations about the quality of the separation including the peak evaluation approach (horizontal baseline and peak height), the authors have done due diligence to explore potential problems and demonstrated method performance. As a result, I recommend this method for Official First Action.

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