NTT Microsystem Integration Laboratories, Atsugi 240198, Japan.
Sensors (Basel). 2012;12(6):7095-108. doi: 10.3390/s120607095. Epub 2012 May 29.
We have successfully developed a surface plasmon resonance (SPR) measurement system for the on-site immunoassay of real samples. The system is composed of a portable SPR instrument (290 mm(W) × 160 mm(D) × 120 mm(H)) and a microfluidic immunoassay chip (16 mm(W) × 16 mm(D) × 4 mm(H)) that needs no external pump system. An integrated vertical capillary tube functions as a large volume (150 μL) passive pump and a waste reservoir that has sufficient capacity for several refill operations. An immunoassay was carried out that employed the direct injection of a buffer and a test sample in sequence into a microfluidic chip that included 9 antibody bands and 10 reference reagent bands immobilized in the flow channel. By subtracting a reliable averaged reference sensorgram from the antibody, we effectively reduced the influence of the non-specific binding, and then our chip successfully detected the specific binding of spiked IgG in non-homogeneous milk. IgG is a model antigen that is certain not to be present in non-homogeneous milk, and non-homogeneous milk is a model of real sample that includes many interfering foreign substances that induce non-specific binding. The direct injection of a real sample with no pretreatment enabled us to complete the entire immunoassay in several minutes. This ease of operation and short measuring time are acceptable for on-site agricultural, environmental and medical testing.
我们成功开发了一种用于现场实时样品免疫分析的表面等离子体共振（SPR）测量系统。该系统由一个便携式 SPR 仪器（290mm(W)×160mm(D)×120mm(H)）和一个微流控免疫分析芯片（16mm(W)×16mm(D)×4mm(H)）组成，无需外部泵系统。一个集成的垂直毛细管作为一个大体积（150μL）的无源泵和一个废物储存器，其容量足以进行几次填充操作。进行了免疫分析，通过顺序将缓冲液和测试样品直接注入包括 9 个抗体带和 10 个固定在流道中的参考试剂带的微流控芯片中。通过从抗体中减去可靠的平均参考传感器图，我们有效地减少了非特异性结合的影响，然后我们的芯片成功地检测到非均相牛奶中特异性结合的 IgG。IgG 是一种确定不存在于非均相牛奶中的模型抗原，而非均相牛奶是一种包含许多诱导非特异性结合的外来干扰物质的真实样品模型。无需预处理直接注射真实样品，使我们能够在几分钟内完成整个免疫分析。这种易于操作和短的测量时间可用于现场农业、环境和医学检测。
