Conducting Polymers, Hydrogels and Their Composites: Preparation, Properties and Bioapplications

Abstract

This review is focused on current state-of-the-art research on electroactive-based materials and their synthesis, as well as their physicochemical and biological properties. Special attention is paid to pristine intrinsically conducting polymers (ICPs) and their composites with other organic and inorganic components, well-defined micro- and nanostructures, and enhanced surface areas compared with those of conventionally prepared ICPs. Hydrogels, due to their defined porous structures and being filled with aqueous solution, offer the ability to increase the amount of immobilized chemical, biological or biochemical molecules. When other components are incorporated into ICPs, the materials form composites; in this particular case, they form conductive composites. The design and synthesis of conductive composites result in the inheritance of the advantages of each component and offer new features because of the synergistic effects between the components. The resulting structures of ICPs, conducting polymer hydrogels and their composites, as well as the unusual physicochemical properties, biocompatibility and multi-functionality of these materials, facilitate their bioapplications. The synergistic effects between constituents have made these materials particularly attractive as sensing elements for biological agents, and they also enable the immobilization of bioreceptors such as enzymes, antigen-antibodies, and nucleic acids onto their surfaces for the detection of an array of biological agents. Currently, these materials have unlimited applicability in biomedicine. In this review, we have limited discussion to three areas in which it seems that the use of ICPs and materials, including their different forms, are particularly interesting, namely, biosensors, delivery of drugs and tissue engineering.

Self-Assembly of Organic Nanomaterials and Biomaterials: The Bottom-Up Approach for Functional Nanostructures Formation and Advanced Applications

“…Polymer co-networks (nanogels and hydrogels) consist of cross-linked polymeric networks that contain both hydrophilic (or polar) and hydrophobic monomer units, that are able to swell their volume in response to (internal) environment changes or external stimuli [99][100][101]. The hydrogel properties can be modified to match the requirements of specific applications by selecting the polymers type (and length), the cross-linking method.…”

“…The hydrosoluble Poly(N-isopropylacrylamide) (PNIPAM), Chitosan, Poy(vinil alcohol), alginate hydrogels are among the most intensely investigated polymer systems for advanced biomedical applications [101,102]. The main applications of stimuli-responsive hydrogels include microactuators and microfluidic devices, electrolyte batteries, artificial muscles and superadsorbents [100][101][102]. The pH-responsive gels have been mainly employed for hydrophilic drug delivery.…”

Uptake and Release of Species from Carbohydrate Containing Organogels and Hydrogels

“…The swelling/deswelling capability of depends on the crosslinking ratio, the less cross-linked gel takes less time to swell than the more highly cross-linked gels. Reversible swelling and de-swelling of gels is a useful property for a variety of applications (e.g., coatings on medical devices) [38][39][40]. Consequently the ability of the organogels to reversibly swell/dry (using DCM as the organic solvent) were studied; similarly, we studied the ability of the hydrogels to reversibly swell/dry (using water), in both cases observing this to be reversible for five rounds of swelling/drying ( Figure A2).…”

Electrochemical DNA Sensor Based on the Copolymer of Proflavine and Azure B for Doxorubicin Determination

“…In these reactions initiated by primary electron transfer, oligomeric products are formed and deposited on the electrode as a dense uniform film, whose properties are derived from those of the monomers [3][4][5]. In most cases, electropolymerized products play role of heterogeneous mediators of the electron transfer or of the matrix wiring the bioreceptors and the nanomaterials (metals, carbon nanoparticles) [6][7][8] and providing the immobilization of biochemical components [9,10]. They offer many advantages over conventional modifiers used for the same purpose.…”