Two methods for glass surface modification and their application in protein immobilization

Protein immobilization is a crucial step in protein chip, biosensor, etc. Here, two methods to immobilize proteins on glass surface were analyzed, one is silanization method using 3-aminopropyltriethoxysilane (APTES), and the other is hydrophobin HFBI coating. The modified glass surfaces were characterized with X-ray photoelectron spectroscopy (XPS), water contact angle measurement (WCA) and immunoassay. The results of XPS and WCA illustrated that the surface property of glass can be changed by both the two methods. The following immunoassay using microcontact printing (μCP) verified that both methods could help protein immobilization effectively on glass slides. Compared with the amine treatment, it is concluded that hydrophobin self-assemblies is a simple and generic way for protein immobilization on glass slides, which has potential application in protein chips and biosensors.