Fabrication of three-dimensional carbon microelectrodes for electrochemical sensing

Carbon microelectrodes have a wide range of applications because of their unique material properties and biocompatibility. The aim of the research work carried out in this thesis was to develop three-dimensional (3D) carbon microelectrodes for electrochemical applications. Three different fabrication processes were established for fabrication of 3D carbon microelectrodes using UV photolithography followed by pyrolysis. UV exposure at three different wavelengths 365 nm, 313 nm and 405 nm was optimized to fabricate suspended 3D epoxy polymer templates. The polymer template was pyrolysed at high temperature to obtain the corresponding carbon microelectrodes. The fabricated microelectrodes are characterized for their physical, electrical and electrochemical properties. The pyrolysis process was optimized for low electrical resistance and high mechanical stability. To explore the application of carbon microelectrodes four different model systems (Glucose sensing, Yeast analysis, Dopamine detection in human stem cell and bone cell monitoring) were tested. In all the model systems 3D carbon microelectrodes showed a 2-3 folds higher sensing signal when compared to 2D carbon electrodes.