MODULAR SURFACE PLASMON RESONANCE BIOSENSOR FOR IN-VITRO DETERMINATION OF PROTEIN

该项目将电动（EK）方法与表面等离子体共振（SPR）光谱相结合，构建了一个灵活的模块化芯片实验室平台，用于确定目标生物标志物。小体积通道被蚀刻到介电衬底中，其中EK方法用于将目标分析物从其它分析物中浓缩和分离（即介电泳和电泳捕获）。 使用生物流体中的化合物来调节样品以进行SPR检测。例如，将采用介电泳和电泳捕获来局部浓缩微流体通道中的靶分析物，同时使干扰蛋白的局部浓度最小化。金传感垫可用于直接无标记SPR分析，涂有生物受体以增加灵敏度 和选择性，或者用生物受体包被用于分析，随后用另一种针对靶生物标志物的抗体进行信号放大。用于信号增强的方法，例如抗体夹心测定将包括在芯片实验室设计中，以实现更高程度的灵敏度。该传感器将应用于心肌梗死生物标志物的检测。 所提出的平台提供了有利于任何生物测定的以下属性： ·模块化的、基于"芯片"的传感平台可以分离、浓缩和量化面板测定所需的多种蛋白质和肽生物标志物。 ·电动方法和SPR检测与夹心测定都适用于分析蛋白质和肽的生理水平。 ·该系统非常适合小体积分析。EP和DEP在直径约10至100微米的小通道中效果最好。SPR对金传感垫200 nm内的折射率变化敏感。 ·EK可以根据电泳迁移率从复杂混合物中快速分离和浓缩分析物。高分辨率的分离是可能的，1000倍的预浓缩可以实现与介电泳或可寻址的电泳捕获。

This project combines electrokinetic (EK) methods with surface plasmon resonance (SPR) spectroscopy to construct a flexible, modular lab-on-a-chip platform for determination of target biomarkers. Small volume channels are etched into a dielectric substrate where EK methods for concentration and separation (i.e. dielectrophoresis and electrophoretic capture) of target analytes from the other compounds in the biofluids are employed to condition the sample for SPR detection. For example dielectrophoresis and electrophoretic capture will be employed to locally concentrate the target analytes in the microfluidic channel while minimizing the local concentration of interfering proteins. Gold sensing pads can be employed for direct label-free SPR analyses, coated with bioreceptors to increase sensitivity and selectivity, or coated with bioreceptors for the analysis followed by signal amplification with the another antibody to the target biomarker. Methods for signal enhancement such as antibody sandwich assays will be included with the lab-on-a-chip design to achieve a greater degree of sensitivity. This sensor will be applied to detection of biomarkers for myocardial infarction. The proposed platform offers the following attributes beneficial to any bioassay: • The modular, 'chip' based sensing platform can separate, concentrate, and quantify multiple protein and peptide biomarkers required for a panel assay. • Electrokinetic methods and SPR detection with sandwich assays are both appropriate for analyzing physiological levels of proteins and peptides. • The system is ideally suited for small volume analyses. EP and DEP work best in small channels approximately 10 to 100 microns in diameter. SPR is sensitive to refractive index changes within 200 nm of the gold sensing pads. • EK can rapidly separate and concentrate analytes from complex mixtures based on electrophoretic mobility. High resolution separations are possible and 1000-fold preconcentration can be achieved with dielectrophoresis or addressable electrophoretic capture.