Biochemical Sensors Utilizing Cavity Ring-Down Spectroscopy

【摘要】zaremps -0313996本探索性研究小额资助（SGER）奖支持对基于空腔衰荡光谱的传感器作为凝聚态生物分子探针的新兴技术的适用性进行研究，特别强调潜在的生物恐怖主义制剂。为了将腔衰荡光谱（CRDS）的超高灵敏度应用于生物传感器技术，将采取四种发展策略。每种方法在实现、选择性和灵敏度方面都有自己的潜在优势。第一种方法是使用一个电池，其入口和出口窗口在布鲁斯特角，以减少吸收损失，当插入光学腔内。这种装置的目的是使探测器小型化，以便能够分析非常小体积的液体。这种设备在与微分离相结合时，如毛细管电泳或芯片实验室，具有特别的前景。第二种方法是使用光学腔，其中光通过倏逝波与周围环境进行光学接触。该装置对光学接触表面的吸收变化很敏感。它的优点是保持光线在内部，因此它不受与表面接触的介质浊度问题的影响。第三种方法是利用表面等离子体共振（SPR）耦合CRDS。它对液面界面也很敏感，其值将取决于分析物敏感探针分子与SPR中使用的金属（金或银）表面耦合的难易程度。第四种方法是液体与构成光学腔的两个反射镜直接接触。这是迄今为止最容易实施的方法，将评估是什么限制了其操作，特别是在分析物选择性方面。该研究为生物分子的检测和定量提供了广泛而重要的应用基础。这项活动得到数学和物理科学理事会多学科活动办公室和生物科学理事会生物基础设施司仪器和仪器开发方案的联合支持。

AbstractZareMPS-0313996This Small Grants for Exploratory Research (SGER) award supports research into the applicability of the newly emerging technique of Cavity Ring-Down Spectroscopy - based sensors as probes for biomolecules in the condensed phase, with particular emphasis on potential bioterrorism agents. Four developmental strategies will be pursued to bring the extraordinary sensitivity of Cavity Ring-Down Spectroscopy (CRDS) to biosensor technology. Each has its own potential advantages for implementation, selectivity, and sensitivity. The first approach is the use of a cell whose entrance and exit windows are at Brewster's angle to minimize absorption losses when inserted inside an optical cavity. The purpose of this device is to miniaturize the detector so that very small volumes of liquid can be analyzed. Such a device has particular promise when coupled to microseparations, such as capillary electrophoresis or lab on a chip. The second approach is the use of an optical cavity in which the light makes optical contact with the surroundings by means of an evanescent wave. This device is sensitive to absorption changes at the surface where the optical contact is made. It has the advantage of keeping the light on the inside so that it is immune to questions of turbidity in the medium in contact with the surface. The third approach is the use of surface plasmon resonance (SPR) coupled to CRDS. It is also sensitive to the liquid-surface interface and its value will depend on the ease with which analyte-sensitive probe molecules can be coupled to the metal (gold or silver) surface used in SPR. The fourth approach is the direct contact of the liquid with the two mirrors that constitute the optical cavity. This approach is by far the simplest to implement, and an assessment will be made of what limits its operations, particularly in regard to analyte selectivity. This research could well provide the basis for broad and important applications in the detection and quantification of biomolecules. This activity is jointly supported by the Office of Multidisciplinary Activities in the Directorate for Mathematical and Physical Sciences and by the Instrumentation and Instrument Development Program in the Division of Biological Infrastructure in the Directorate for Biological Sciences.