Advances in Molecularly Imprinted Polymers Based Affinity Sensors (Review)

Abstract

Recent challenges in biomedical diagnostics show that the development of rapid affinity sensors is very important issue. Therefore, in this review we are aiming to outline the most important directions of affinity sensors where polymer-based semiconducting materials are applied. Progress in formation and development of such materials is overviewed and discussed. Some applicability aspects of conducting polymers in the design of affinity sensors are presented. The main attention is focused on bioanalytical application of conducting polymers such as polypyrrole, polyaniline, polythiophene and poly(3,4-ethylenedioxythiophene) ortho-phenylenediamine. In addition, some other polymers and inorganic materials that are suitable for molecular imprinting technology are also overviewed. Polymerization techniques, which are the most suitable for the development of composite structures suitable for affinity sensors are presented. Analytical signal transduction methods applied in affinity sensors based on polymer-based semiconducting materials are discussed. In this review the most attention is focused on the development and application of molecularly imprinted polymer-based structures, which can replace antibodies, receptors, and many others expensive affinity reagents. The applicability of electrochromic polymers in affinity sensor design is envisaged. Sufficient biocompatibility of some conducting polymers enables to apply them as "stealth coatings" in the future implantable affinity-sensors. Some new perspectives and trends in analytical application of polymer-based semiconducting materials are highlighted.

Keywords: DNA-sensors; affinity sensors; biosensors; conducting polymers (CPs); electrochemical deposition; electrochemical sensors; electrochromic organic polymers; immunosensors; molecularly imprinted polymers (MIPs); polymer-modified electrodes.

Figure 1

Formation of polypyrrole by glucose oxidase assisted polymerization, figure from reference [45].

Figure 2

Formation of conducting polymer (A—polyaniline, B—polypyrrole, C—polytiophene) layers around redox enzyme–glucose oxidase, which during catalytic action is producing H₂O₂ that in here presented polymerization reactions is acting as an initiator. Adapted from [38].

Figure 3

Principle scheme of formation composite structure consisting of polyaniline (PANI), gold nanoparticles (AuNPs) and glucose oxidase (GOx) PANI/AuNPs-GOx, which is followed by cyclic voltammetry-based investigation. Adapted from [56].

Figure 4

The scheme of Ppy electrochemical deposition by potential pulses and entrapment of proteins within the formed Ppy layer, figure from reference [45].

Figure 5

(A) Chrono-amperograms, registered during electrochemical deposition of polypyrrole by potential-pulse mode. (B) Dependence of anodic peaks on the pulse number during electrochemical deposition, figure adapted from reference [12].

Figure 6

Representation how protein imprinted MIP sensor sensors are designed and are acting, 1—extraction of imprinted proteins, 2—action of MIP based sensor in the solution containing similar proteins. Adopted from [2].