Spatially resolved analysis of photobioelectrochemical reactions on quantum dot based electrode architectures

这个联合研究项目的目的是制造新的光生物电化学传感结构和它们的详细表征。为此，应利用量子点（QDs）与电极的耦合以及量子点上的特定酶反应。计划在多传感器应用中研究所有子组件的各自特性。首先是胶体纳米颗粒（NPs）。除了量子点外，混合量子点也将用于特定物质的检测灵敏度控制。此外，将更详细地研究量子点电极界面，并研究各种电极设计，包括无机半导体NPs的氢化多层。一个主要的课题是在量子点电极上固定各种具有高活性和可控空间分辨率的酶。这种生物混合系统的特性应根据其分析传感器应用的潜在用途进行检查。一个方面是在酶层中嵌入额外的金属颗粒，以便通过辐照（等离子体加热）局部控制温度。这可能导致改善电极信号在量子点电极。除了基于固定化酶消耗氧气或生成过氧化氢的系统外，还将研究量子点内产生的电荷载流子与酶中的氧化还原反应的耦合。为此，将开发基于聚合物的改进界面设计。最后，我们计划构建一个多传感器系统，在该系统中，不同的酶在空间上被分离，并结合在一个包裹有量子点的工作电极上。酶的底物转化应通过光指针选择性地读出，从而能够对各种分析物进行平行分析。

The aim of this joint research project is the fabrication of new photobioelectrochemical sensing architectures and their detailed characterization. For this purpose the coupling of quantum dots (QDs) with electrodes and specific enzyme reactions at the QDs shall be utilized. It is planned to investigate all subcomponents regarding their individual characteristics in a multiple sensor application. This starts with the colloidal nanoparticles (NPs). Beside QDs also hybrid NPs will be utilized in order to control specifically the detection sensitivity for certain substances. Further, the QD electrode interface will be inspected in more detail and various electrode designs including hydrid multilayers of inorganic semiconductors NPs will be examined. A major topic is the defined immobilization of various enzymes with high activity and controlled spatial resolution on a QD electrode. The properties of such biohybrid systems shall be examined in terms of their potential use for analytical sensor applications. One aspect is the embedding of additional metallic particles in the enzyme layer in order to locally control the temperature by irradiation (plasmonic heating). This may lead to improved electrode signals at the QD electrodes. In addition to systems that are based on the consumption of oxygen or the generation of hydrogen peroxide by the immobilized enzymes, also the coupling of generated charge carriers within the QDs and the redox reactions in the enzymes will be studied. To this end, an improved interface design will be developed based on polymers. Finally, it is planned to build a multiple sensor system, in which different enzymes are spatially separated bound onto a working electrode coated with QDs. The substrate conversion at the enzymes shall be read out selectively by means of a light pointer, hence enabling a parallel analysis of various analytes.