A new technique to detect antibody-antigen reaction (biological interactions) on a localized surface plasmon resonance (LSPR) based nano ripple gold chip

•The nano ripple LSPR chip has monolayer molecule-coating sensitivity and specific selectivity.•Gold nano-ripple sensing chip is a low cost, and a label-free method for detecting the antibody-antigen reaction.•The plasmonic resonance shift depends upon the concentration of the biomolecules attached on the surface of the nano ripple pattern.