Recently, researchers have been frequently using a biosensor-based gold chip couple detection method. The gold surface is modified for various materials including self assembly monolayer (SAM), biotin, streptavidin, dextran, Prolinker, protein G, lipid bilayer, etc. for use as a biosensor, diagnosis system. The modified gold surface can enhance the immobilization amounts, orientation, activity, and stability of the receptor, and decrease the nonspecific binding. Surface plasmon resonance (SPR) is made of optical biosensors that are widely gaining recognition as a valuable tool to investigate biological interactions. The key features of SPR biosensors make this technology suitable for a wide range of applications. We have SPR system of fluidic type. Our SPR system can detect biomolecules-biomolecules or biomoleculessensor surface interaction. A biosensor for the detection of small molecules or diagnostic markers requires high sensitivity. One of the methods for enhancing sensitivity is a surface modification to provide a bioadaptable space. In this study, we modified the surface of a bare gold chip by using our NHS-SAM for enhancing of the detection sensitivity, and we compared its results with a commercial SAM. We also observed the antigenantibody interaction and compared its results using an SPR analyzer.
