Surface Measurement Related on Surface Pasmon Resonance Sensing

表面等离子体共振(SPR)传感器是一种有用的分析设备，它可以使用金薄膜测量分析物和传感器芯片之间的表面反应。我们的研究目的是开发实用的SPR传感器，以便更广泛地应用于大多数生物样品的分析。为此，需要基于以下两种方法实现高灵敏度的测量：1)为了通过物理方法实现SPR传感器的高灵敏度响应，开发了两种新型的SPR传感器。i)微光纤SPR传感器：通过化学方法在光纤表面粘贴一根掺锗的光纤，并通过气相沉积在光纤表面沉积一层50 nm厚的薄金层。这种微型SPR传感器可以测量到1皮升体积样品，反射率值在10-3个数量级变化。ii)平板光波导(SOWG)SPR传感器：多次光学反射是达到高灵敏度检测极限的有用方法。A5…采用玻璃薄膜作为传感器芯片，制作了10 mm以上的SOWG-SPR传感器。传感器芯片有一层50 nm的薄金层，也可以用作伏安测量的电极。将含有二茂铁的自组装单分子膜(FC-SAM)固定在传感器芯片表面，用SPR传感和伏安法检测氧化还原反应。在这种情况下，可以通过两种方法进行实时分析来测量氧化还原反应。用SPR方法可以准确地测定氧化还原反应产物。2)通过化学方法实现SPR传感器响应的高灵敏度：传统的商品化SPR传感器通常测量反射指数(RI)值的实部。另一方面，我们阐明了在SPR测量中测量RI值虚部的有用性。基于对基于虚部RI测量的方法学的理论理解，制备了一种基于吸收的SPR传感器。因此，该方法被应用于测定低分子物质，如葡萄糖，这些物质通常很难用传统的SPR传感器检测到。此外，还制备了一种能够放大SPR响应的聚合物纳米颗粒，作为SPR传感器的化学放大标记剂，用于高灵敏度的免疫传感

A surface plasmon resonance (SPR) sensor is a useful analytical device that can measure a surface reaction between an analyte and a sensor chip using a gold thin film. Our research purpose is to develop practically useful SPR sensors for wider applications for the analysis of mostly biological samples. For this purpose, highly sensitive measurements are required that can be realized based on the two methods as listed below.1) For realizing high sensitivity in SPR sensor response by physical methods, two new types of SPR sensors were developed.i) Micro-fiber SPR sensor:A germanium-doped optical silica fiber was chemically attached and a thin gold layer of 50nm thickness was placed on the fiber surface by vapor deposition. This micro-SPR sensor can measure down to one picoliter volume sample with reflective index value changes at the 10-3 order level.ii) Slab optical waveguide (SOWG) SPR sensor:Multiple optical reflections are a useful way to reach a highly sensitive detection limit. A5 … More to 10mm SOWG-SPR sensor was made using a glass film as the sensor chip. The sensor chip has a 50nm thin gold layer that can also be used as an electrode for voltammetric measurements. A ferrocene-containing self-assembled monolayer (FC-SAM) was immobilized on the sensor chip surface and the redox reaction was measured by both SPR sensing and voltammetric methods. In this case, real time analysis can be performed to measure redox reactions by both methods. The redox reaction products can be accurately determined with the SPR method.2) Realizing high sensitivity in SPR sensor response by a chemical method:Aconventional commercialized SPR sensor is normally measuring the real part of the reflective index (RI) value. On the other hand, we have clarified the usefulness of measuring the imaginary part of the RI value in the SPR measurement. An absorption-based SPR sensor was prepared relying on the theoretical understanding of the methodology based on imaginary part RI measurements. Consequently, the method was applied to determine low molecular weight substances, such as glucose, which are normally difficult to detect with a conventional SPR sensor. Furthermore, a polymer nanoparticle, which can amplify the SPR response, was prepared as a chemical amplification labeling reagent for a SPR sensor, that is useful for immuno-sensing with high sensitivity Less