Résumé
Reference materials are one of the major approaches to achieve measurement accuracy and metrological comparability. Different functions of reference materials should also be distinguished when applied to mass spectrometry as an emerging technology in clinical laboratory. Proper reference materials for validation, calibration and quality control of measurement method can ensure the accuracy and comparability of test results. Based on the problems of reference materials in clinical mass spectrometry, the precautions for the use of reference materials are summarized in the aspects of measurement method validation, calibrator usage and quality control.
Résumé
Vitamins are classified as either fat-soluble (vitamins A, D, E, K) or water-soluble (vitamins B and vitamin C). Traditional methods of immunoassay have only been developed for vitamins D,B6, B9 and B12. However, they cannot distinguish between vitamin subtypes such as D2, D3 and associated epi isomers (which has higher leveks in infants),giving false positive or negative results. Mass spectrometry has become a gold standard method for small molecule analysis in biological samples with its advantages in speed,resolution,sensitivity and specificity. It is widely used in clinical research and diagnosis and provides an efficient method for simultaneous detection of multivitamins in one injection using one low volume sample collection.