Surface development of molecularly imprinted polymer films to enhance sensing signals

• New trends in chemosensing using molecularly imprinted polymers (MIPs).
• Importance of the control over the ratio of surface area to volume.
• Preparation of MIPs with the high (surface area)-to-volume ratio.
• Analytical parameters of MIP chemosensors.

Molecular imprinting of polymers is a well-established procedure for preparing artificial recognition units of chemical sensors. This procedure can produce materials of selectivity comparable to that of their biological counterparts. Deposition of a thin film of a molecularly imprinted polymer (MIP), playing a role of recognition unit, directly on surface of the transduction unit integrates these units to result in a chemical sensor. However, a smooth and continuous thin film of such a unit limits sensitivity of the devised chemosensor because of slow diffusion of an analyte through the film towards less accessible imprinted molecular cavities in the film bulk on the one hand and a low specific surface area on the other. Therefore, this area should be increased in a controllable way by developing the film surface. For that, macroporous MIP with large surface area, deposited directly on a transducer surface, effectively enhance signals in sensing applications. This review describes in detail a growing trend to prepare MIPs with a high (surface area)-to-volume ratio to enhance the sensing signal.