Microarray technology has dramatically advanced the study of protein interactions leading to discovery and validation of new biomarkers and therapeutic drugs. Typically, protein microarrays are pre-spotted with target molecules in one device and then tested with probe molecules using another device. During each testing cycle, the entire microarray becomes exposed to the probe molecules. Though this approach has been shown to be effective for some applications, it inherently suffers from several key limitations that hinder it from gaining broader utility: 1) both the printing and analysis steps consume large sample volumes, which is particularly problematic where only small amounts of proteins are available or affordable; 2) the exposure of sample solution to the entire microarray restricts the kinetic interaction analysis of only one probe to N targets (1XN interactions only), significantly limiting the types of applications and analytical power of microarrays; and 3) complete microarrays must be pre-printed blindly with no feedback on spot uniformity, target activity, or probe selectivity which may lead to inconclusive data, unnecessary tests, and delays in obtaining effective results. We propose an Integrated Microarray Printing and Detection System (IMPDS) to address the key limitations restricting the analytical power and broader appeal of microarray technology. IMPDS will have the ability to incorporate feedback of microarray formation and testing in order to generate more relevant results sooner, perform high resolution droplet-based testing with ultra-low nanoliter volume samples, conduct a more versatile M x N (many-to-many) protein kinetic interaction analysis of high density microarrays, and measure molecular interactions and binding kinetics in cell-based microarrays. IMPDS relies upon the careful integration of two core technologies into a single instrument: 1) a novel ultra-low volume piezoelectric liquid dispensing system and 2) a proprietary, high-resolution, distortion-free surface plasmon resonance imaging (DF-SPRi) system. The success of this project will lead to a new commercializable microarray technology capable of: 1) streamlining microarray spotting and detection into a single instrument for simpler, faster, more accurate results, 2) ultra-low volume nanodroplet-based analysis of high density microarrays, 3) flexible and multiplexed M x N label-free protein interaction kinetic analyses in real time, 4) cell-based microarray analyses with single cell resolution. This project will bring together strengths from Biosensing Instrument Inc. (BI) an innovator and global supplier of high-performance SPR instruments, and from the Center for Bioelectronics and Biosensors, the Biodesign Institute at Arizona State University (ASU), inventors of the piezoelectric liquid dispensing technology. Together we will develop IMPDS into a powerful tool for commercial use in high-throughput protein interaction studies leading to the discovery and validation of new molecular diagnostic biomarkers and new therapeutic drugs.
This project aims to develop an integrated microarray printing and detection system (IMPDS) that enables high-throughput analysis of protein interactions kinetics in microarray or whole-cell based formats. By use of droplet-based reactions, IMPDS can measure many to many molecular interactions with a single device. The success of this project will lead to a powerful tool to study protein interactions leading to the discovery and validation of new molecular diagnostic biomarkers and new therapeutic drugs.
| Yin, L L; Wang, S P; Shan, X N et al. (2015) Quantification of protein interaction kinetics in a micro droplet. Rev Sci Instrum 86:114101 |
