Abstract:

The patterning and immobilization of protein molecules onto functionalized silicon substrate through surface silane chemistry is of interest because protein patterning is an important prerequisite for the development of protein-based diagnostics in biological and medicinal fields. As a model system, mesoscale netty lysozyme arrays were assembled on oxidized undecyltrichlorosilane (UTSox) monolayer coated silicon surface through nanosphere lithography. The size of the arrays ranged from nanometer to micrometer can be easily adjusted by changing the size of nanospheres applied on the surface. By using nanosphere lithography, we are capable of fabricating a regular array of protein islands over centimeter sample regions. The created lysozyme protein patterns were characterized by atomic force microscopy (AFM) and fluorescence microscope, respectively. The analysis has demonstrated that this newly established approach offers a faster and more reliable process to fabricate netty protein arrays over large areas compared to conventional scanning-probe based fabrication methods. Furthermore, the carboxylic acid-terminated layer on surfaces is particularly effective for immobilizing protein molecules through either electrostatic interactions or covalent attachment via imine bonds. Therefore, the negative-toned protein structure on the surface with carboxylic acid groups coated on the bare areas makes it possible to fabricate two types of protein molecules on one surface.

Key words: Nanosphere lithography, Lysozyme, Netty array, Self-assembled monolayer, Atomic force microscopy, Fluorescence microscope