A simple process for selective bio-functionalization of SU-8 surface for Lab-on-a-Chip applications

SU-8 is a popular epoxy based negative photoresist developed by IBM. It has been widely used as structural material in Bio-MEMS and Lab-on-a-Chip devices due to its bio-compatible properties. SU-8 surface has hydrophobic nature. Often it is made to be hydrophilic for microfluidic transport and bio-functionalization purposes. Selective functionalization and permanent hydrophilicity are most desired for Lab-on-a-Chip application and increased shelf life of devices. There are few proven process to achieve a selective and stable hydrophilic SU-8 surfaces. In this work we extend these processes and functionlize the SU-8 surface with Biotin molecules as a proof of concept. The immobilized biotin can be used to detect Avidin and Streptavidin molecules. Relevant surface characterization results would be furnished to prove the process. This simple process has greater potential in manufacturing of Lab-on-a-Chip and Biosensor devices