Surface plasmon resonance (SPR) imaging system is presented as a novel technique based on modified Mach-Zehnder phase-shifting interferometry (PSI) for biomolecular interaction analysis (BIA), which measures the spatial phase variation of a resonantly reflected light in biomolecular interaction. In this technique, the micro-array SPR biosensors with over a thousand probe NDA spots can be detected simultaneously. Owing to the feasible and swift measurements, the micro-array SPR biosensors can be extensively applied to the nonspecific adsorption of protein, the membrane/protein interactions, and DNA hybridization. The detection sensitivity of the SPR PSI imaging system is improved to about 1 pg/mm 2 for each spot over the conventional SPR imaging systems. The SPR PSI imaging system and its SPR sensors have been successfully used to observe slightly index change in consequence of argon gas flow through the nitrogen in real time, with high sensitivity, and at high-throughout screening rates.

A novel surface plasmon resonance (SPR) imaging system based on modified Mach-Zehnder phase-shifting interferometry (PSI) measures the spatial phase variation of a resonantly reflected light in biomolecular interaction. In this technique, the SPR DNA microarray can diagnose the target DNA without additional labeling in real-time biomolecular interaction analysis (BIA). Owing to the feasible and swift measurements, the SPR microarray with this SPR imaging system can be extensively applied to the nonspecific adsorption of protein, the membrane-protein interaction, receptor-ligand interaction, DNA hybridization. The detection limitation of the SPR PSI imaging system is improved to about 1 pg/mm 2 surface coverage of biomaterial for each individual spot over that of the conventional SPR imaging system that observe the intensity variation of a resonantly reflected light. The SPR PSI imaging system and its SPR microarray can provide the capability to analyze DNA hybridization or protein interaction in real-time, with high resolution, and at high-throughout screening rates.