A NEW METHOD FOR THE ANALYSIS OF VITAMIN D

描述（由申请人提供）：大多数临床检测从实验室采集血液开始。盖茨基金会和许多其他基金会已经认识到并试图解决这样一个事实，即世界上许多地方的临床试验都是在原始环境中进行的。即使在美国，抽血师在实验室抽血准备血清或血浆以供分析，这种奢侈在许多医疗点并不普遍。这一提议的最重要的组成部分是，世界将获得一种等离子体提取技术，这种技术可以在没有能源或人为干预的情况下产生少量可重复的等离子体。此外，以这种方式收集的2.5或6 μ L血浆样品可以通过快递或邮件在收集盘上干燥运输到中心实验室。提出的实现这一目标的技术是基于血液分离，通过正面负载的微型膜组合，其中血浆通过毛细管作用在多个膜层中运输。在大约3分钟的时间里，当血浆迁移到膜堆底部直径6.4 mm的收集盘时，血细胞通过吸附和过滤的组合被去除。剥离（分层）上层承载细胞的膜层，从系统中暴露出装载血浆的收集盘，该收集盘在大约10分钟内干燥。这些干燥的样品可以在24小时内从世界上几乎任何地方运送到实验室进行分析。这种血浆提取技术正在开发和验证，作为维生素D类似物质谱分析的组成部分。作为第一阶段提出和开发的维生素D测试的一部分，开发了一种试剂（SecoSET），可以高选择性地衍生维生素D物种。SecoSET的功能是赋予维生素D永久正电荷，从而提高其在电喷雾电离质谱中的电离效率，同时降低其LOQ。

DESCRIPTION (provided by applicant): Most clinical assays begin with blood collection in a laboratory setting. The Gates foundation and many others have recognized and attempted to deal with the fact that in much of the world clinical testing is done in a primitive setting. The luxury of having a phlebotomist to draw blood with a laboratory to prepare serum or plasma for analysis is not universal at many points-of-care, even in America. The most significant component of this proposal is that the world will obtain a plasma extraction technology that produces a small, reproducible aliquot of plasma without an energy source or human intervention. Moreover, 2.5 or 6 �L plasma samples collected in this manner can be transported dry on a collection disc to a central laboratory by courier or mail. The technology proposed to accomplish this is based on blood fractionation by frontal loading of a miniature assemblage of membranes where plasma is transported through multiple membrane layers by capillary action. Blood cells are removed via a combination of adsorption and filtration as plasma migrates to a 6.4 mm diameter collection disc at the bottom of the membrane stack during roughly three min. Stripping (delaminating) the upper, cell bearing membrane layers from the system exposes the plasma loaded collection disc which dries in roughly 10 min. These dried samples can be transported from almost anywhere in to world to a laboratory for analysis within 24 hr. This plasma extraction technology is being developed and validated as component of a mass spectrometry (MS) analysis of vitamin D analogues. As part of the vitamin D test proposed and developed in Phase I, a reagent was developed (SecoSET) that derivatizes vitamin D species with high selectivity. The function of SecoSET is to impart a permanent positive charge to vitamin D species that increases their ionization efficiency in electrospray ionization MS and concomitantly reduces their LOQ.