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

开发真实的检测和表征生物分子在其生理环境中的相互作用的方法，而不使用外来标签或标记物如荧光染料或缀合酶，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、检测传染因子和环境毒素，和药物的开发。还期望测量异质介质如生物相容性纳米多孔或微孔结构材料（例如二氧化硅、二氧化钛、氧化铝）中的这些相互作用，因为这样的介质原则上可以提供精确水平的传感器灵敏度，因为它们提供高表面积以增加受体的附着密度，并且可以操纵表面能和孔径以提供选择性吸附。当前基于光学的传感器然而，SPR和蛋白质芯片需要平面结构用于检测，并且与多孔膜不相容，因为光学散射总是伴随着这种材料。微波源的稳定性和可调谐性为高灵敏度的信号幅度和相位测量创造了机会，这些信号的频率至少可达20 GHz，可用于探测在大动态范围内以高精度实现微小的介电变化。 最近，它表明，特定的分子结合发生在界面上的事件可以通过微波介电光谱检测。如果微波结构可以优化（设计和材料），并用于明确的识别低浓度的分析物的特异性结合，没有外在的标签，该技术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，因此该技术具有光学手段无法解决的潜在应用。虽然这一初步的发展是有前途的，它提出了几个重要的问题：（i）什么是电磁相互作用的性质，发生在微波域，导致检测和识别的分子事件发生在一个微波大分子层？(ii)微波结构是否可以被设计和优化以提供相对于光学生物传感器的竞争优势，从而直接检测和区分不同的结合事件？该提案汇集了三个小组的互补优势，并得到了他们机构的支持（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的专业知识），目标是实施，表征和分析微波结构，以研究界面处生物分子结合的实时检测，区分和定量。该跨学科团队将开发平面微波传输线结构，与介观流体系统集成，利用日益复杂的模型免疫蛋白结合试验来研究电磁相互作用，这些电磁相互作用表明在平面（2D）界面和多孔材料（3D材料）内部发生的特定结合事件。双传输线结构将用于减少外部影响，否则可能会掩盖检测和识别的结合事件。介电色散的变化与结合事件将在各种微孔材料和结构的形态和表面能已被控制，以稳定受体，可以捕获特定的生物分子进行研究。这个多学科的项目沉浸在研究，超越微波工程，生命科学和有机，无机和聚合物化学之间的界限的学生。学生将接触到两个主要的工业研究组织（安捷伦和IBM Almaden研究）的哲学，并获得他们的人员和资源。

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.