Abstract
Surface Plasmon Resonance (SPR) has been widely studied for various application. Due to the highly sensitive optical property to the change of the refractive index of the surrounded medium, there have been lots of reports for biological sensing. Direct Plasmon-to-Electric conversion device using metal nanostructures and semiconductor does not require additional readout optics and the device size and sensing area could be much smaller (1/100 to 1/10 of size) than current technologies. In addition, our sensing platform designed to address the issue of using the colored medium (e.g. whole blood) for detection. The detection signal comes only from plasmonic absorption and is not affected by the absorption from the medium. We developed a plasmonic sensing platform using a metal-semiconductor-metal detector by incorporating gold nanostructures on top of the semiconducting layer. The gold nanostructures are functionalized using antibodies to detect Troponin I, which is very important molecule to prevent hart attacks. In this presentation, we report a successful demonstration of a point-of-care sensing platform to detect cardiac Troponin I using antibody functionalized plasmonic nanostructures. Because the sensors are integrated into a microfluidic channel, it requires only a few µl of sample volume. The limit of detection was 20 pg/ml in our preliminary results, and we successfully demonstrated sensor operation using whole blood. This plasmonic sensor has several advantages such as extremely small size for the point-of-care system, multiplexing capability, no need of complex optical geometry and real-time binding monitoring.
