New cysteamine based functionalization for biochip applications

A new versatile chemistry on gold surface has been developed and studied with a Surface Plasmon Resonance Imaging system. It is based on a monolayer of homobifunctional cross-linker 1,4 phenylenediisothiocyanate (PDC) modified with neutravidin bounded onto a gold film coated with a self-assembled monolayer of β-mercaptoethylamine (cysteamine). Using this surface chemistry, a DNA microarray affinity sensor has been developed. Specificity, regenerability and surface homogeneity were quantified and successfully applied to both synthetic oligonucleotides and PCR-amplified products DNA–DNA interactions.