Biocompatible interfaces for biosensors

Abstract

Electrochemical biosensors need to interface reliably with complex biological samples. The latter are characterized by high surface activity and the presence of numerous interferent molecules. Polymeric membranes through their ability to act as surface modifiers of biosensors and as selective barriers help to minimize selectivity and biocompatibility problems for biosensors. Membranes studied include those based on PVC, polyether sulphone and cellulose acetate variously incorporating surfactants and as unmodified films to create a spectrum of permeabilities and surface properties. Additionally, electropolymerized phenolics as thin films have been tested as surface modifiers for base Pt working electrodes. Polypyrrole loaded with protein affinity molecules can register impedimetric change following target molecule binding – the avidin–biotin model system was used to exemplify this. Ultimately, fluid flow over a device can create a fully biocompatible, selective interface and operational viability was tested in preliminary studies using microfluid flow channels.

Keywords:

• PVC
• Cellulose acetate
• Polyphenol
• Polypyrrole
• Microfluidic
• Biosensor
• Electrochemical
• Biocompatibility

Acknowledgements

The authors would like to thank EPSRC-RSC, JDFI, BDA and the EU for funding of the ongoing studies presented in this review.