Amphiphilic copolymers consisting of an all conjugated polythiophene backbone and sparsely attached oligo-ε-caprolactone side chains have been prepared.

Composite i-PP/PEDOT films made of isotactic polypropylene (i-PP), which is frequently used for the fabrication of implantable medical devices for internal use, and chemically synthesized poly(3,4-ethylendioxythiophene) (PEDOT) nanoparticles, which are electroactive and biocompatible, have been prepared and used to detect biofilm infection. After chemical and morphological characterization, the properties (interfacial, mechanical, thermal and electrochemical) and biocompatibility of i-PP/PEDOT have been examined. Besides, carbon screen-printed electrodes coated with i-PP/PEDOT have been found to detect the growth of Gram-positive and Gram-negative bacteria through the oxidation of nicotinamide adenine dinucleotide (NADH), which comes from the bacteria metabolism (i.e. the respiration). Thus, as outer bacterial membranes are permeable to cytosolic NADH, this metabolite has been found to be an appropriated target for the detection of growing bacterial infections (biofilms). In addition, the sensor does not respond towards eukaryotic cells. This is because the major NADH pool in eukaryotic cells is located at the mitochondria and, therefore, the concentration of in the medium is not high enough to be detected since the inner mitochondrial membrane is impermeable to NADH or NAD+.

Development of smart functionalized materials for tissue engineering has attracted significant attention in recent years. In this work we have functionalized a free-standing film isotactic polypropylene (i-PP), a synthetic polymer...

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New amphiphilic poly(ethylene glycol) (PEG)-grafted random intrinsically conducting copolymers which combine three different functionalities have been engineered, prepared and characterized. Specifically, these "rod-coil" type copolymers bear conducting polypyrrole (PPy) and poly(Schiff base) (PSB) sequences randomly distributed in their backbones; hydrophilic grafted side chains consisting of well-defined PEG chains are attached to the PSB units. Basically, the synthesis of the copolymers is conducted sequentially by employing the "macromonomer" technique via electrochemical co-polymerization of a bis ( pyrrole) benzoic Schiff base-containing PEG macromonomer with pyrrole monomers. After investigation of the chemical and electrochemical properties of the synthesized copolymers, their advantages of multi-functionality in terms of biomedical applications have been demonstrated. More specifically, the conjugated PPy and PSB sequences enabled the grafted copolymers to exhibit great ability to catalyse the oxidation of serotonin, an important neurotransmitter found in blood platelets and in the central nervous systems of animals and humans. On the other hand, the enhanced biocompatibility in comparison with bare PPy is due to the presence of PEG side chains, while bacteriostatic activity against both Gram-negative and Gram-positive bacteria is imparted by the synergistic combination of the polycationic character of the PPy main chain with the benzoic Schiff base functional groups and with the bent-shaped architecture of the facially amphiphilic PSB sequences, respectively. Accordingly, these grafted copolymers are promising materials for developing implantable electrodes for serotonin detection which present the abovementioned characteristics. c "Petru

The electro-chemo-mechanical response of robust and flexible free-standing films made of three nanoperforated poly(lactic acid) (pPLA) layers separated by two anodically polymerized poly(3,4-ethylenedioxythiophene) (PEDOT) layers, has been demonstrated. The mechanical and electrochemical properties of these films, which are provided by pPLA and PEDOT, respectively, have been studied by nanoindentation, cyclic voltammetry and galvanostatic charge-discharge assays. The unprecedented combination of properties obtained for this system is appropriated for its utilization as a Faradaic motor, also named artificial muscle. Application of square potential waves has shown important bending movements in the films, which can be repeated for more than 500 cycles without damaging its mechanical integrity. Furthermore, the actuator is able to push a huge amount of mass, as it has been proved by increasing the mass of the passive pPLA up to 328% while keeping unaltered the mass of electroactive PEDOT.

Robust and flexible free-standing films made of spin-coated poly(lactic acid) (PLA) and poly(3,4-ethylenedioxythiophene) (PEDOT) nanolayers have been prepared. A steel sheet coated with a sacrificial layer of PEDOT:poly(styrenesulfonate) (PSS) and a spincoated nanolayer of PLA was used as working electrode for the anodic polymerization of 3,4-ethylenedioxythiophene monomer. The latter was only successfully accomplished when rounded-shape nanoperforations of average diameter 4914 nm were introduced into PLA layers, which was achieved by combining the phase segregation processes undergone by immiscible PLA:poly(vinyl alcohol) (PVA) mixtures with selective solvent etching to remove PVA domains. Nanoperforations allowed the utilization of the semiconducting PEDOT:PSS sacrificial layer to immobilize the electropolymerized PEDOT chains. Morphological and topographical studies show the templating effect of PEDOT layers. In addition of flexibility and mechanical strength, free-standing 5-layered films present good electrochemical activity, evidencing their potential ability to reversibly exchange ions with the medium.These properties offer important advantages with respect to those of neat PLA and supported PEDOT films, as has been illustrated by cell culture and protein adsorption assays. Cell cultures evidenced the superior behavior of 5-layered films as bioactive platforms for fibroblast and epithelial cells proliferation, while adsorption assays reflected their potential as selective bioadhesive surfaces for protein separation.

Design of an amphiphilic heterografted block copolymer composed of a hydrophobic core backbone and both hydrophilic side chains, able to detect the redox reaction of NADH.