GOALI: Dielectric Microwave Spectroscopy of Macromolecular Recognition Events in Differential Transmission Lines

0245716 Knoesen开发实时检测和表征生理环境中生物分子之间相互作用的方法，而不使用外部标记或标记，如荧光染料或结合酶，对于绘制导致疾病状态的生化途径，监测患者的临床相关分析物，检测感染性病原体和环境毒素，以及药物的开发具有重要意义。还需要在非均相介质中测量这些相互作用，例如生物兼容的纳米孔或微孔结构材料(例如，二氧化硅、二氧化钛、氧化铝)，因为这种介质原则上可以提供极高水平的传感器灵敏度，因为它们为增加受体的附着密度提供高表面积，并且可以控制表面能量和孔大小以提供选择性吸附。然而，目前基于光学的传感器(SPR和蛋白质芯片)需要平面结构来进行检测，并且由于此类材料总是伴随着光学散射，因此与多孔膜不兼容。近年来，微波源在光谱纯度、稳定性和可调性方面的改进为高灵敏度测量高达20 GHz的信号的幅度和相位创造了机会，可以用于在大动态范围内高精度地检测微小的介电变化。最近有研究表明，通过微波介电光谱可以检测到发生在界面上的特定分子结合事件。如果微波结构可以优化(设计和材料)，并用于明确识别低浓度分析物的特定结合，而不需要外部标签，该技术将有可能彻底改变生物分子检测。此外，正如本项目中提出的，由于微波可以询问光学不透明区域，该技术具有无法通过光学手段解决的潜在应用。虽然这一初步发展是有希望的，但它提出了几个重要的问题：(I)在微波域中发生的导致检测和识别发生在超薄大分子层中的分子事件的电磁相互作用的性质是什么？(Ii)能否设计和优化微波结构以提供相对于光学生物传感器的竞争优势，以直接检测和区分不同的结合事件？这项建议结合了三个小组在其机构(加州大学戴维斯分校；微波测量和光谱学，IBM-Almaden；材料研究，安捷伦实验室；分子检测和微波仪器方面的专业知识)的支持下的互补优势，目标是实施、表征和分析微波结构，以研究界面生物分子结合的实时检测、区分和量化。这个跨学科的团队将开发与介观流体系统集成的平面微波传输线结构，该结构利用日益复杂的免疫蛋白结合模型分析来研究电磁相互作用，这些相互作用表明发生在平面(2D)界面和多孔材料(3D材料)中的特定结合事件。将使用双传输线结构来减少外部影响，否则可能会模糊对绑定事件的检测和识别。与结合事件相关的介电色散变化将在各种微孔材料和结构中进行研究，这些材料和结构的形态和表面能量已被控制以稳定能够捕获特定生物分子的受体。这个多学科的项目使学生沉浸在超越微波工程、生命科学和有机、无机和聚合物化学之间的研究中。学生们将接触到两个主要工业研究组织(安捷伦和IBM Almaden Research)的理念，并接触到他们的人员和资源。

0245716KnoesenThe development of methods to detect and characterize interactions between biomolecules in their physiological environments, in real time, and without the use of extrinsic tags or markers such as fluorescent dyes or conjugated enzymes is of great interest to map biochemical pathways that lead to disease states, monitor patients for clinically relevant analytes, detect infectious agents and environmental toxins, and the development of drugs. It is also desirable to measure these interactions in heterogeneous media such as biocompatible nanoporous or microporous structured materials (e.g. silica, titania, alumina) since such media could, in principle, provide an exquisite level of sensor sensitivity as they provide high surface areas for increased attachment density of receptors, and the surface energy and pore sizes can be manipulated to provide selective adsorption. Current optical-based sensors (SPR and protein chips), however, require a planar configuration for detection and are not compatible with porous films because of the optical scattering invariably accompanying such materials.Recent improvements in the spectral purity, stability and tunability of microwave sources are creating the opportunity for highly sensitive magnitude and phase measurements of signals up to at least 20 GHz that can be used to detect subtle dielectric changes with high accuracy over a large dynamic range. Recently it was shown that specific molecular binding events occurring at an interface can be detected by microwave dielectric spectroscopy. If microwave structures could be optimized (design and materials) and used for unambiguous identification of specific binding of low concentration analytes without extrinsic tags, the technique has the potential to revolutionize biomolecular detection. Furthermore, as is proposed in this project, since microwaves can interrogate optically opaque regions, the technique has potential applications that cannot be addressed by optical means. While this initial development is promising, it raises several important questions: (i) what is the nature of the electromagnetic interaction that occurs inthe microwave domain that leads to the detection and identification of a molecular event that occurs in an ultrathin macromolecular layer? (ii) can microwave structures be engineered and optimized to provide a competitive advantage over optical biosensors to directly detect and distinguish between different binding events?This proposal brings together the complementary strengths of three groups with the support of their institutions (UC Davis; microwave measurements and spectroscopy, IBM-Almaden; materials research, Agilent Laboratories; expertise in molecular detection and microwave instrumentation) with the goal of implementing, characterizing, and analyzing microwave structures to investigate real-time detection, differentiation and quantification of biomolecular binding at interfaces. This interdisciplinary team will develop planar microwave transmission line structures, integrated with meso-fluidic systems, that make use of model immunoprotein binding assays of increasing complexity to investigate the electromagnetic interactions which indicate specific binding events occurring at planar (2D) interfaces and inside porous materials (3D materials). Dual transmission line structures will be used to reduce external effects thatcould otherwise obscure the detection and identification of a binding event. The dielectric dispersion changes associated with binding events will be studied in various microporous materials and structures of which the morphology and surface energies have been controlled to stabilize receptors that can entrap specific biomolecules.This multi-disciplinary project immerses students in research that transcends the boundaries between microwave engineering, the life sciences and organic, inorganic and polymer chemistry. The students will be exposed to the philosophies of two major industrial research organizations (Agilent and IBM Almaden Research) and gain access to their personnel and resources.