Immobilization of angiotensin II and bovine serum albumin on strip-patterned ZnO nanorod arrays.

For an effective protein immobilization for highly sensitive biosensors, we determined the binding properties and characteristics of angiotensin II and bovine serum albumin on the surface of patterned ZnO nanorod arrays (NRAs) which were selectively grown on desired areas of Si substrates. The surfaces of ZnO NRAs were modified by 3-aminopropyltriethoxysilane and gluteraldehyde, and the activated NRAs were then conjugated with angiotensin II protein and bovine serum albumin. The silanization process and conjugation of protein were verified by secondary ion mass spectroscopy (SIMS) and X-ray photoelectron spectroscopy (XPS) techniques. The immobilizing densities of proteins determined by Coomassie protein assay were 4.5 microg/cm2 for angiotensin II and 5.3 microg/cm2 for bovine serum albumin.