The Electrical Contacting of Enzymes in Mediator-functionalized Sol-gel Matrices

The Electrical Contacting of Enzymes in Mediator-functionalized Sol-gel Matrices 

Sol—gel matrices are ideal candidates for the construction of enzyme-containing matrices. They are chemically inert, resist swelling, are processed at low temperatures, and have tunable porosity [77]. To date, silicon alkoxide 

The electrical characteristics of these films can be improved by the incorporation of electroconductive materials such as carbon powder or metal particles into the mixture (Fig. 14b). The electrodes prepared with these additions benefit from the porosity and rigidity of the silica matrix and from the electrical conductivity of the additive [77]. 

Composite sol-gel electrodes containing GOx and coimmobilized redox mediators have been applied for the preparation of glucose biosensors [111-115]. In these procedures, the redox mediator is either added during the gellification process (resulting in its physical entrapment in the silicate structure) [112] or is chemically bound to the silicate network (e.g. Ai-(3-trimethoxysilylpropyl) ferrocenylacetamide (18) may be used as a functionalized comonomer) [114, 

The electron relay may also be tethered to the protein backbone prior to the synthesis of the matrix. Relay-functionalized GOx has heen entrapped in composite graphite/sol-gel matrices [113, 

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