Vitamin B12 (cyanocobalamin) in Infant Formula Adult/Pediatric Nutritional Formula by Liquid Chromatography with Ultraviolet Detection: Collaborative Study, Final Action 2014.02

To determine the repeatability and reproducibility figures of the AOAC First Action Official MethodSM 2014.02 (Vitamin B12 in Infant Formula and Adult/Pediatric Formula by Liquid Chromatography with UV Detection), a collaborative study was organized. Twenty-one laboratories located in 13 different countries agreed to participate. The study was divided into two parts. During the first part, the laboratories analyzed two samples in duplicate by using the method described in the protocol. The laboratories that provided results within the expected range were qualified for part two, during which they analyzed 10 samples in blind duplicates. Eighteen laboratories managed to provide results on time for reporting. The results were compared with the Standard Method Performance Requirement (SMPR® 2011.005) established for vitamin B12. The precision results met the requirements stated in the SMPR except for one sample. Repeatability and reproducibility relative standard deviation ranged from 1.1 to 6.5% and from 6.0 to 23.8%, respectively, with only one matrix showing reproducibility values higher than the required 11%. Horwitz ratio values were all well below 2 (0.17–0.78). The AOAC Expert Review Panel (Stakeholder Panel for Infant Formula and Adult Nutritional Expert Review Panel) determined that the data presented met the SMPR and, hence, recommended the method to be granted Final Action status in September 2016.