NSF Award
1509799
1- Proposal Title: Proposal #1509746<br/>Collaborative Research: A self-contained microfluidic optical cavity biosensing platform for multiplex label-free molecular diagnostics<br/><br/>2- Brief description of project Goals: <br/>We aim to demonstrate a self-contained microfluidic optical cavity sensor which enables simple, cost-effective, label-free and highly sensitive biomarker screenings.<br/><br/>3- Abstract:<br/><br/>3a. Nontechnical:<br/>Millions of people suffer from major chronic diseases such as cancers, diabetes, cardiovascular and pulmonary disease, and infectious disease. To improve survival rates of patients and give the right treatment at the right time, early diagnosis of these diseases is required. The most common way to diagnose these diseases is to use a biochemical test that measures the presence or concentration of a macromolecule in a solution through the use of an antibody. The current gold standard biochemical test for detecting these biomarkers is called an enzyme linked immunosorbent assay (ELISA). Such tests have significant limitations with respect to the required sample volume, total testing time, expensive fluorescence detection and an inability to test for many biomarkers simultaneously. A simpler and more cost effective approach is still needed to achieve a more efficient biochemical testing platform. In this research project, we will demonstrate a novel optical cavity biosensor, a sensor that detects the concentration of biomarkers with simple two partially reflecting mirror structure, integrated with a simple microfluidic device. This integrated device enables automated, low-cost, and highly sensitive sensing which is required for various molecular diagnostic fields. Such rapid, simple and cost effective label-free biosensors have the potential to transform the field of early disease screening and to make significant impact on various clinical and healthcare applications. In addition, a new bio-sample handling technique will be implemented to make overall testing procedures simple.<br/>The education and outreach activity of this project is well-aligned with the research approach and outcomes. By educating undergraduate and graduate students through summer research experiences, new courses, and seminars, we will be able to deliver the state-of-art techniques related with micro/nanotechnologies. More specifically, by adapting the use of microfluidic system and optic sensors into new courses, we will enhance hands-on learning of microfabrication and semiconductor/microfluidic processes. For K-12 students, we will use this advanced biosensing tool for STEM education. Real demonstration of this work will be broadened through the development and distribution of educational activities on the optical physics and micro-flow phenomena. <br/><br/>3b. Technical:<br/>A standard ELISA process includes a laborious and time-consuming sample preparation and labeling processes that involve complicated multi-step chemical reactions, expensive fluorescence and laser equipment to detect a labeled molecule. A simpler and cost effective approach is still needed to achieve a more efficient immunoassay platform. By developing optical cavity biosensor arrays, we will achieve the ultimate goal in biosensors which is a combination of label-free, low cost, high sensitivity, and high selectivity. In addition, adapting a differential detection method with multiple diode systems enables a multiplexing immunoassay, enhances the sensor`s sensitivity and increases the linear dynamic range. By integrating the optical cavity sensor with the self-contained microfluidic platform, we will design SMDx (self-contained multiplexable label-free diagnostics) to achieve a label-free, multiplexable microfluidic molecular diagnostic system. In this platform, various bioassay protocols can be implemented using pumpless technology. Furthermore, the SMDx platform can be readily extended to a portable system by incorporating a modular biosensing system for reliable medical diagnostics.<br/><br/>This project has multiple aims:<br/> (1) Develop an affordable point-of-care biosensor using optical cavity structure enabling multiplexing bioassay with high sensitivity.<br/>(2) Understand sensitivity enhancement by increasing the responsivity of the transducer through the differential detection method. <br/>(3) Demonstrate a seamless microfluidic device containing passive flow control with channel surface properties and wicking force.<br/>(4) Implement a self-contained multiplex label-free diagnostics (SMDx) platform for cardiac panel screenings.
