Although silica sol-gel derived glass is an insulator and does not participate in redox rections, it can be used for modification of the electrode surface  or can be applied as a inert support for bulk modified electrode, most frequently carbon ceramic composite electrode (CCE) . The use of silicate matrix opens numerous possibilities for electrode modification. This is because of relatively simple chemistry of silicates and availability of organically modified precursors of sol-gel process. One can tune the electrode properties as hydrophobicity/hydrophilicity or incorporate redox activity by modification of silicate matrix pore walls by functional groups Also the porosity of this material can be adjusted by selection of the sol-gel process conditions. Finally, the native enzymes or tissue cells can be easily incorporated into silicate matrix without loosing their activity, opening the many possibilities of amperometric biosensor preparation .
The preparation of silicate modified electrodes and their application as amperometric sensors will be reviewed. These will incluse pH sensing, gas sensing, stripping analysis and biosensing. The advantages, disadvantages, capabilities and promises of silicate modified electrodes will be discussed.
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