Conducting polymers antibody immobilization

The application of conducting polymers such as polyaniline, polypyrrole, and polythiophene for immobilizing capture antibodies in immunoassay systems is widespread. 

An electrochemical immunosensor includes a transducer (a current-conductive strip deposited on a polymer substrate) and a biorecognition substance (an antigen or antibodies) immobilized on the transducer surface. The formation of an immune complex and localization of non-antigen-specific antibodies (proteins) on this complex, which are usually labeled with enzymes, and a substrate in the solution, generates an active species capable of generating an electrochemical response. The sequential process, the use of enzymes, and occasionally unstable substrates limit and complicate a wide-scale application of such sensors. 

Sargent and Sadik [84] have proposed that there are four steps involved in the current generation at an antibody-immobilized conducting polymer electrode ... 

The most widely investigated systems in terms of sensor desi are the detection of glucose, molecular recognition based on polynucleotides, and antigen/antibody interactions. Table I provides a summary of the type of immobilization, the conducting polymer used, and the parameter measured for a number of the analytical tools that have been developed over the last few years. 

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