Abstract: A new surface plasmon resonance imaging(SPRi) system was designed and fabricated using a right angle trapezoid prism as SPR coupler, which allows the fixation of left optical elements in a compact space and addition of a 1—2× zooming adjuster. This design simplifies the angle scanning mechanism, enables a very fine adjustment of incident angle from 40° to 80° at 0.001° angle resolution, and makes the observation possible of size-variable chips(1—4 cm²), providing a lateral spatial resolution up to 3600 Point/cm². Its sensiti-vity was evaluated with sucrose solutions, giving the data up to 7×10^-6 RIU(Refractive index unit). A linear relationship was obtained between resonance angle and sample refractive index, with correlation coefficients of 0.99953. The new system has been further validated in the immuno-reaction of BSA with anti-BSA, which enables to produce both of kinetic reaction curves and differentiated dot images. These results indicate that the newly designed SPRi system is highly promising for high-through binding affinity applications.

Key words: Surface plasmon resonance imaging setup, Fixed-optical, Wide variable incident angle, Rightangle trapezoid prism coupler