A novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for quick and efficient quantification of...

Deficiencies in fat-soluble vitamins (FSVs) have been linked to various systemic disorders. In this study, we introduce a novel and straightforward assay for the analysis of FSVs, suitable for large-scale sample screening while reducing laboratory testing costs.

The method, termed sodium-acetonitrile extraction (SoAce), was developed and validated for the quantification of selected FSVs, including Vitamin A (retinol), Vitamin D2 (25-hydroxyvitamin D2), Vitamin D3 (25-hydroxyvitamin D3), Vitamin E (α-tocopherol), and Vitamin K1 (phylloquinone). A saturated sodium chloride solution combined with acetonitrile was employed as the extraction reagent. Mass spectrometric detection was carried out using a triple quadrupole mass spectrometer in positive ion mode via an APCI source. Method validation was conducted in accordance with Chinese regulatory guidelines and the C62-A standard.

Using the SoAce-liquid chromatography-tandem mass spectrometry (LC-MS/MS) approach, FSVs were successfully separated and quantified within 30 min. The assay demonstrated excellent linearity, with all regression coefficients exceeding 0.996. The lower limit of quantification (LLOQ) was determined as 12.5 ng/mL for Vitamin A, 0.31 ng/mL for Vitamin D2, 1.56 ng/mL for Vitamin D3, 625 ng/mL for Vitamin E, and 0.08 ng/mL for Vitamin K1. Specificity, stability, accuracy, and precision were all evaluated and met the required validation criteria. A comparative analysis against an existing commercial FSV kit using the same instrumentation revealed strong correlation, with coefficients ranging from 0.928 to 0.962.

The developed SoAce-LC-MS/MS method fulfills the requirements for rapid and reliable assessment of FSV status in human serum. Further studies are warranted to fully explore the potential applications and clinical utility of this assay.