Determination of Taurine in Infant Formula and Adult/Pediatric Nutritionals by Ultra High-Performance Liquid Chromatography with Multiple Reaction Monitoring-Mass Spectrometry: Single-Laboratory Validation, First Action 2022.08.

Background: Taurine (2-aminoethanesulfonic acid) is an essential β-amino acid, which is one of the most abundant intracellular amino acid component in humans. The level of free taurine in human milk is higher than in bovine milk. Since taurine is considered important for the development of a newborn, fortification of infant nutrition with taurine is common. This publication describes a rapid method for the determination of taurine in infant formula and adult/pediatric nutritionals.

Objective: This publication demonstrates the suitability and applicability of the method to determine taurine content in infant formula and adult/pediatric nutritionals.

Methods: Test portions are deproteinized by acid in an aqueous environment prior to analysis. The level of taurine is analyzed by hydrophilic interaction chromatography (HILIC) coupled with multiple reaction monitoring MS (MRM-MS). Quantitation is accomplished using a stable isotope-labeled internal standard (SILS) for taurine.

Results: The accuracy of the method was validated using standard reference materials and spike recovery studies. The average recoveries ranged between 92% and 105%. The relative standard deviation repeatability (RSDr) and relative standard deviation intermediate precision (RSDiR) were in the range of 0.7-4.6% (RSDr) and 1.3-6.7% (RSDiR). The limit of quantitation (LOQ) was below the requirement of 0.5 mg/100 g.

Conclusion: The single-laboratory validation (SLV) of the method for determination of taurine content in infant formula and adult/pediatric nutritionals demonstrates that it meets the requirements per AOAC INTERNATIONAL Standard Method Performance Requirements (SMPR) 2014.013.

Highlights: A fast method to selectively determine the content of taurine in infant formula and adult/pediatric nutritionals was evaluated and found to be fit for purpose for routine product compliance testing. Based on the results of this SLV, the method was approved by the AOAC Stakeholder Program on Infant Formula and Adult Nutritionals (SPIFAN) Expert Review Panel for SPIFAN Nutrient Methods for First Action Official MethodsSM status.