A disposable polymer sensor chip combined with micro-fluidics and surface plasmon read-out

Abstract

This paper describes a new type of disposable polymeric sensor chip based on the grating coupling of surface plasmon modes combined with a micro-fluidic channel system. A specifically designed silicon stamp with nano-structure (grating) on the micro-structures (micro-channel) was fabricated by combining a holographic method and photolithography. By using such a stamp the micro-channels, the grating coupler and the gold which was first thermally evaporated onto the stamp were transferred to the polymeric substrate successfully in one step. It is demonstrated that the grating profile in the micro-channels allowed a very efficient coupling of the laser light to the surface plasmons propagating at the bottom of the micro-channels. The transferred gold exhibits properties of a freshly cleaned surface, and the self-assembly of a functional thiol derivative (mercapto-PEG) onto the sensor chip can be monitored by surface plasmon spectroscopy. The results obtained in this sensor chip show no difference from those obtained on a regular grating-coupled SPR sensor chip.