Fabrication Of Micropatterned Graphene And Its Regulation To Nerve Cell Growth Fabrication Of Micropatterned Graphene And Its Regulation To Nerve CellGrowth

Micropatterned graphene (RGO) not only has the unique structure and excellent performance of RGO film, but also possesses special space arrangement structure, which makes RGO be widely used in electronic element, chemical sensor and biosensor, etc. Therefore, how to fabricate uniform sized, well-shaped RGO array is the key of practical application of RGO array. In this thesis, the microfabrication technology and electrochemical method were combined to manufacture the patterned graphene oxide (GO) array and RGO/GO array, which were further applied to the biological detection and induction of cell proliferation. Specific summarized as follows:1. The lithography technology and polydimethylsiloxane (PDMS) transfer technology were used for the preparation of GO pattern. The GO array was further electrochemically reduced to RGO array. In lithography, better quality of micropatterned GO film could be obtained at the GO concentration (?0.4mg/mL) by controlling the concentration of spin-coating GO solution. Micropatterned GO films with 7nm-.15nm- and 23nm-thick were obtained by controling the thickness and rotation rate of photoresist. In PDMS transfer print, a well-patterned GO film with 40nm-thick was achieved by applying a pressure of 94.4?102.4N/cm-2 on the PDMS substrate for 12h. Besides, the RGO array electrochemically reduced from GO possessed good electrical conductivity and light penetration, whcih could be fabricated "interdigital" electrodes and other electronic components with ?A- or nA-current response. The GO surface had a large number of oxygen-containing functional groups, such as carboxyl, hydroxy, epoxy and so on. which maked it hydrophilic and therefore showed good biological activity. The GO/ITO array realized the regulation to the induced migration, differentiation and proliferation of MG63 and PC 12 cells.2. The lithography technology combined with electrochemical method was used for the preparation of RGO/GO microarray electrodes. First, the RGO/GO microarray exhibited a sigmoid-shaped voltammogram, suggesting the micro-electrode array (MEA) behavior of rGO-based array electrode. By adjusting the array structure, electrochemical reduction time and catalytic voltage, the RGO/GO array exhibited better activity and detection ability to hydrogen peroxide oxidation in the conditions of 20?m-diameter disc with a pitch of 60?m,30s reduction time and 0.6V catalytic voltage. The detection concentration of hydrogen peroxide had a linear relation with the oxidation current in the range from 1×l0-3mol L-1 to 100×10-3mol L-1 and from 2×10-6mol L-1 to 100×10-6mol L-1,with the detection limit of 667nM and the sensitivity of 26.78nA mm-2mM-1. This realized the detection of hydrogen peroxide on RGO array without loading enzyme and nanoscaled catalyst. Secondly, GO and RGO could regulate the selective growth of cells and affected the migration, growth and proliferation of cells on the RGO/GO array. Our results showed that the cells tended to preferentially grow on GO surface with their tentacles fixed on the interface between GO and RGO. The RGO/GO array could be succeedfully used as MEA for the detedtion of cell secretion of hydrogen peroxide.