Micro-array detection system for gene expression products based on surface plasmon resonance imaging

A kind of micro-array detecting system based on SPR imaging has been developed. The light source of this system is a semiconductor laser. The light emitted from the source becomes round and parallel after going through a pinhole and being collimated. This parallel light beam arrives at a polarizer, its s-light component is shielded and p-light component passes through. The p-light component which is of a rectangular shape after going through a rectangular slip is cast onto the glass surface of a sensing chip, and generates an evanescent wave which excites surface plasmon resonance (SPR). The SPR images are accepted by a 2D CCD camera and processed in real time by a computer. The chips are made into bare gold film array by photoetching and cause the linker layer to cover the gold thin film by self-assembling. Then, rabbit IgG is immobilized onto the liker layer, which finished the preparation of array sensing chip. Once the sensing chip is installed, the detecting system begins the investigation of the interaction between rabbit IgG and its antibody. The experimental results indicate that the 2D SPR biosensor is able to detect a number of units in real time for gene expression products. The improvement of technology and the increase of array number can realize high throughput detection, which is significant to proteomics study and new drug discovery and development.