Enabling a microfluidic immunoassay for the developing world by integration of on-card dry reagent storage
Enabling a microfluidic immunoassay for the developing world by integration of on-card dry reagent storage
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DOI：
10.1039/b811158h
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发表时间：
2008-01-01
期刊：
影响因子：
6.1
通讯作者：
Yager, Paul
中科院分区：
文献类型：
--
作者：
Stevens, Dean Y.;Petri, Camille R.;Yager, Paul
作为为发展中国家创建即时诊断系统的努力的一部分，我们提出了一种具有卡上干试剂存储的微流体流通膜免疫测定。通过保留试剂功能，无水试剂的储存和复溶使器械能够在具有挑战性的、不受管制的环境条件下保持活力。该测定在一次性层压卡上进行，该层压卡包含用捕获分子图案化的多孔膜和包含无水分析物标记的纤维垫。为了进行测定，将卡放置在外部泵送和成像仪器中，该仪器能够以受控的流速将样品和再水化试剂递送到测定膜以产生定量结果。使用疟疾抗原恶性疟原虫富组氨酸蛋白II（PfHRP 2）作为模型，我们证明了选择干燥储存条件，试剂再水化的表征，和执行的自动化卡上检测。在各种糖基质中干燥的金-抗体缀合物显示在高温下储存60天后保留其活性的80-96%，并且在微流体通道中流动下表征重构试剂的释放曲线。该系统在9分钟内给出了亚纳摩尔范围内的检测限，显示出扩展到人类血液样本的定量多分析物分析的潜力。
As part of an effort to create a point-of-care diagnostic system for the developing world, we present a microfluidic flow-through membrane immunoassay with on-card dry reagent storage. By preserving reagent function, the storage and reconstitution of anhydrous reagents enables the devices to remain viable in challenging, unregulated environmental conditions. The assay takes place on a disposable laminate card containing both a porous membrane patterned with capture molecules and a fibrous pad containing an anhydrous analyte label. To conduct the assay, the card is placed in an external pumping and imaging instrument capable of delivering sample and rehydrated reagent to the assay membrane at controlled flow rates to generate quantitative results. Using the malarial antigen Plasmodium falciparum histidine-rich protein II (PfHRP2) as a model, we demonstrate selection of dry storage conditions, characterization of reagent rehydration, and execution of an automated on-card assay. Gold-antibody conjugates dried in a variety of sugar matrices were shown to retain 80-96% of their activity after 60 days of storage at elevated temperatures, and the release profile of the reconstituted reagent was characterized under flow in microfluidic channels. The system gave a detection limit in the sub-nanomolar range in under nine minutes, showing the potential to expand into quantitative, multianalyte analysis of human blood samples.