McLean Gary R, Soyemi Samson, Ajayi Oluwafunmito P, Fernando Sandra, Sowinski-Mydlarz Wiktor, Stewart Duncan, Illingworth Sarah, Atkins Matthew, Bhakta Dee
School of Human Sciences, London Metropolitan University, London N7 8DB, UK.
National Heart and Lung Institute, Imperial College, London SW7 2AZ, UK.
Methods Protoc. 2025 Aug 1;8(4):85. doi: 10.3390/mps8040085.
Vitamin D is the only vitamin that is conditionally essential, as it is synthesized from precursors after UV light exposure, whilst also being obtained from the diet. It has numerous health benefits, with deficiency becoming a major concern globally, such that dietary supplementation has more recently achieved vital importance to maintain satisfactory levels. In recent years, measurements made from blood have, therefore, become critical to determine the status of vitamin D levels in individuals and the larger population. Tests for vitamin D have routinely relied on laboratory analysis with sophisticated equipment, often being slow and costly, whilst rapid immunoassays have suffered from poor specificity and sensitivity. Here, we have evaluated a new rapid immunoassay test on the market (Rapi-D & IgLoo) to quickly and accurately measure vitamin D levels in small capillary blood specimens and compared this to measurements made using the standard laboratory method of liquid chromatography and mass spectrometry. Our results show that vitamin D can be measured very quickly and over a broad range using the new method, as well as correlate relatively well with standard laboratory testing; however, it cannot be fully relied upon currently to accurately diagnose deficiency or sufficiency in individuals. Our statistical and comparative analyses find that the rapid immunoassay with digital quantification significantly overestimates vitamin D levels, leading to diminished diagnosis of vitamin D deficiency. The speed and simplicity of the rapid method will likely provide advantages in various healthcare settings; however, further calibration of this rapid method and testing parameters for improving quantification of vitamin D from capillary blood specimens is required before integration of it into clinical decision-making pathways.
维生素D是唯一一种条件性必需维生素，因为它在紫外线照射后由前体物质合成，同时也可从饮食中获取。它对健康有诸多益处，维生素D缺乏已成为全球主要关注的问题，因此膳食补充剂最近对于维持适宜水平变得至关重要。近年来，血液检测对于确定个体及更大人群中维生素D水平的状况已变得至关重要。维生素D检测通常依赖于使用精密设备的实验室分析，往往耗时且成本高昂，而快速免疫测定法的特异性和灵敏度较差。在此，我们评估了市场上一种新的快速免疫测定测试（Rapi-D & IgLoo），以快速、准确地测量微量毛细血管血样中的维生素D水平，并将其与使用液相色谱和质谱的标准实验室方法所做的测量结果进行比较。我们的结果表明，使用新方法能够非常快速地在较宽范围内测量维生素D，并且与标准实验室检测结果的相关性相对较好；然而，目前它还不能完全依靠来准确诊断个体的维生素D缺乏或充足情况。我们的统计和比较分析发现，具有数字定量功能的快速免疫测定法显著高估了维生素D水平，导致维生素D缺乏的诊断减少。快速方法的速度和简便性可能在各种医疗环境中具有优势；然而，在将其纳入临床决策路径之前，需要对这种快速方法和检测参数进行进一步校准，以改善从毛细血管血样中对维生素D的定量。
