Protein Lab-on-a-Chips on Polyer Substrates for Point-of-Care Testing (POCT) of Cardiac Biomarkers

Cardiac disease is the major cause of death in patients with end-stage renal disease, accounting for about 40% of all deaths. Cardiovascular diseases account for a significant number of mortalities in the United States especially in the 50 -65 age range. The fast growing numbers of such patients generate great demand for a commercially available lab-on-a-chip which is able to carry out not only fast, reliable, and accurate measurements but also in portable or disposable format at low cost. In this research, a disposable protein lab-on-a-chip on a Cyclic-Olefin Copolymer (COC) is designed, fabricated and calibrated for monitoring human cardiac biomarkers. The multi-analyte protein lab-on-a-chip is able to perform rapid and accurate measurement of multiple cardiac biomarkers in human serum, such as CRP, Myoglobin, c-Tnl and BNP. By integration into a portable analyzer system, point-of-care testing (POCT) of cardiac biomarker measurement can be realized. Comparing with commercially available cardiac biomarker diagnostic systems, this work mainly focuses on an inexpensive platform for disposable biochip applied for multi-analyte point-of-care testing. Many novel methods and technologies are then developed and extensively tested such as low-cost polymer fabrication process and self-spotting antibody patterning. The proposed protein lab-on-a-chip will be able to measure multiple types of cardiac biomarkers in human serum, such as CRP, Myoglobin, c-Tnl and BNP. In the proposed protein lab-on-a-chip, fluorescence and chemiluminescence based solid phase immunoassay techniques will be applied for sensing. In this work, multiple parameters that can affect cardiac biomarker immunoassay performances in protein lab-on-a-chip are extensively studied and used for computer-based simulation. The protein lab-on-a-chip configuration is then characterized and optimized based on the simulation and experimental results. By integration into a portable optical detection system and an automatic microfluidic control system, point-of-care testing of human cardiac biomarkers can be realized. In addition, by adopting different types of antibodies, the proposed protein lab-on-a-chip also can be easily extended to the detection of other biomarkers and proteins for clinical diagnostics. ACKNOWLEDGEMENTS The five-year study of Ph.D study is the most valuable and memorable experience to me. During this period, I received numerous assistances from my advisors, co-workers, lab members, and all of my friends. Without their help, this work would not have been possible. First of all, I would like to express my sincere appreciation to my advisor, Dr. Chong H. Ahn. He provides me with generous encouragement, strict but definitely necessary advice, and invaluable support. His ever-young enthusiasm will always stimulate me in my entire life. Besides being my mentor, he is also very kind and nice to every of his students and make us feel at home. I am highly honored to have him as my advisor. I would like to thank Dr. Jin in Environment Health department who allowed me to use his typhoon scanner to conduct my experiments. I would like to thank Mr. Sperling in serum & Plasma Banking Center who allowed me to use his lab for blood testing and provided the serum sample. Thanks also to Dr. Joseph H. Nevin, Dr. Marc Cahay, Dr. Greg Beaucage, Dr. Paul Bishop, and Dr. Aniruddha Puntambekar for being members of my thesis committee. Many students and staff members have also been extremely important to this work. I would like to thank all students of Dr. Ahn’s group for their support. Finally, I would like to express my gratitude and thanks to my parents for their constant support and encouragement from the other side of Pacific Ocean.