Biomedical sensor platform based on optical microresonator array

在这个项目中，应该建立一个创新的微传感器平台并进行测试，该平台以一种简单的方式将光学微谐振器的高灵敏度与生物化学过程的选择性结合在一起，如抗基因抗体反应。传感器平台由可更换的传感器芯片和读出单元组成。传感器芯片包含尺寸略有不同的光学微谐振器阵列。这些颗粒被覆盖了一层选择性涂层。在激光照射下，一些颗粒表现出强烈依赖于外加波长与颗粒直径之比的光学共振。有些粒子部分处于共振状态，有些则处于非共振状态。因此，粒子以不同的亮度辐射。这形成了一种特有的光强度图案。表面的改变，例如由于物质在颗粒表面上的吸附，导致共振性质的改变，从而导致光强度图案的改变。该特定涂层提供对分析物的选择性吸附。这使得检测分析物成为可能。该图案由一台CCD摄像机记录下来，并由一台联网的PC进行处理。通过链霉亲和素(作为涂层)和生物素(作为分析物)对传感器的性能进行了示例性研究。利用这个平台，应该可以检测到1纳米范围内的物质数量，例如生物素。

Within this project, an innovative microsensor platform should be established and tested, which combines in a simple way the high sensitivity of optical microresonators with the selectivity of biochemical processes, like antigene-antibody reactions. The sensor platform consists of a replaceable sensor chip and the readout unit. The sensor chip contains an array of optical microresonators with slightly different sizes. The particles are coated with a selective layer. Illuminated with laser light, some particles show optical resonances which depend strongly on the ratio between the applied wavelength and the diameter of the particle. Some particles are partly in resonance and some are off resonance. The particles radiate therefore with different brightness. This forms a characteristic light intensity pattern. Changes of the surface, e.g. due to adsorption of substances on the surface of the particle, lead to a change of the resonance properties and therefore of the light intensity pattern. The specific coating provides a selective adsorption of the analyte. This makes it possible to detect the analyte. The pattern is recorded by a CCD-camera and processed by a connected PC. The properties of the sensor are investigated exemplarily by means of the pair Streptavidin (as coating) and Biotin (as analyte). With this platform, it should be possible to detect substance quantities e.g. biotin in the range of 1 nM.