A disposable nano grating SPR sensor chip for detection of biomolecule concentration

We present a disposable nano-grating SPR (Surface Plasmon Resonance) sensor chip for the detection of biomolecule concentration. The sensor chip has two fluidic channels, each encapsulating a nano-scale grating for SPR sensing. Compared to the previous multi-channel SPR sensors using fiber-optic switches or special prisms, the present SPR sensor chip achieves a compact and inexpensive SPR sensor using an external mirror. For disposable SPR sensors, the fluidic channels with nano- gratings were fabricated by micromolding process. We successfully measured the binding reaction rate for the 2nM ~ 200nM m-antibiotin, thus verifying biomolecule concentration detectability of the nano-grating SPR sensor chip. In addition, the binding reaction rates measured from the present SPR sensor chip agreed well with those from a commercialized SPR sensor. Therefore, the present nano-grating SPR sensor chip offers simple structure and low cost for use in integrated lab-on-a-chip and point-of-care services.