Towards separation-free electrochemical affinity sensors by using antibodies, aptamers, and molecularly imprinted polymers - A review

Affinity assays using antibodies and nucleic acids have been established in research, clinical diagnostics, and industry for many years. The application of nucleic acid arrays in genomics and transcriptomics has become more and more routine. For proteomics, several protein chip systems are already on the market. However, for portable, easy to use, and cost effective devices new measuring principles are needed. Progress has been made in the development of antibody-like molecular recognition elements, which are often more stable than antibodies and which can be used for new signal transduction principles. The review will give an overview of the main recognition elements (antibodies, aptamers, and molecularly imprinted polymers) and measuring principles which are used today in electrochemical affinity assays and sensors.