Fabrication And Modification Of Porous Silicon And Its Application In Microarray

Since the accidental discovery of photoluminescence phenomena of porous silicon, it attracts scientists’ attention and been wildly researched. In another field, under the period of "post genome project", microarray which considered of great importance to life science has made a rapid development. On this paper, with unique properties of high porosity, enormous specific surface area, high chemical activity etc., porous silicon was used as substrate in fabrication of microarray. The research contents are as follows:Uniformly porous silicon substrate with large surface area (12mm×58mm) was successfully prepared by simple double-cell electrochemical etching method. From SEM image of porous silicon prepared under optimal condition, we found that it has a regular nanostructure with pore diameter around15nm. After functionalizing with3-Glycidyloxypropyltrimethoxysilane, epoxide is grafted onto surface of porous silicon successfully.Well-known biomolecular recognition system (the interaction of mouse IgG with rabbit anti-mouse IgG antibody) was chosen here to establish this new microarray format by proof of principle experiments. We found that the detection sensitivity of the mouse IgG microarray was dependent on preparing conditions of porous silicon substrate including etching current density, etching time, and concentration of HF. Under optical conditions (500mA/cmz etching current density,450s etching time and25%HF), specific binding could be detected using rabbit anti-mouse IgG antibody at concentrations as low as10ng/mL with a dynamic range from316ng/mL to10μg/mL. The experimental result demonstrates that the as-prepared porous silicon substrate could be used to fabricate protein microarrays with high reaction capability.After functionalizing with epoxide groups, the porous silicon substrate was used in fabrication of monosaccharide microarray and the interaction of monosaccharide microarray with lectin (Man-α with ConA, Gal-β with RCA) was investigated. The experiment shows that monosaccharide microarray with porous silicon as substrate could be used in investigating the interaction between monosaccharide and lectin.