Periodic Gold Nanohole Arrays Fabricated by Interference Lithography for Optical-Diffraction Biosensing

In this work, an optical-diffraction biosensor consisted of gold nanohole arrays was fabricated by interference lithography and lift-off process. The transmitted first diffraction order intensity of different streptavidin concentrations was analysed using a 458 nm wavelength and a photodetector connected to an oscilloscope. The biosensor limit of detection (LOD) was found to be 122 ng.mL−1. The possibility of real time measurements and the high sensibility achieved demonstrate the great potential of the device.