Simultaneous determination of vitamin A and E in infant formula using a modified QuEChERS approach coupled with ultrahigh-performance liquid chromatography-diode array detection.

The simultaneous determination of vitamin A and E vitamers in complex matrices presents a significant analytical challenge. To address this, we validated a straightforward method based on a QuEChERS pretreatment coupled with ultrahigh-performance liquid chromatography and diode array detection (QuEChERS-UPLC-DAD). The modified QuEChERS pretreatment procedure integrates saponification and extraction processes into a single step, enabling efficient phase separation, reducing analysis time, and eliminating the need for a salting-out step. Notably, this approach simultaneously accomplishes a recovery of 83.2% to 100.5%, a relative standard deviation of less than 4.6%. The accuracy of the proposed QuEChERS-UPLC-DAD method was confirmed through comparison with a UPLC-IDMS/MS method and analysis of a commercial certified reference material (NIST SRM 1869). Importantly, the approach was successfully applied to analyze various complex dairy products, including infant formula, milk, yogurt, and dairy beverages. Therefore, QuEChERS-UPLC-DAD approach is well-suited for routine quality control and nutritional assessment.