Bio-inspired conductive scaffolds composed of sodium hyaluronate containing a colloidal dispersion of water-miscible polyaniline or polypyrrole particles (concentrations of 0.108, 0.054 and 0.036% w/w) were manufactured. For this purpose, either crosslinking with N-(3-dimethylaminopropyl-N-ethylcarbodiimide hydrochloride and N-hydroxysuccinimid or a freeze-thawing process in the presence of poly(vinylalcohol) was used. The scaffolds comprised interconnected pores with prevailing porosity values of ~ 30% and pore sizes enabling the accommodation of cells. A swelling capacity of 92-97% without any sign of disintegration was typical for all samples. The elasticity modulus depended on the composition of the scaffolds, with the highest value of ~ 50 kPa obtained for the sample containing the highest content of polypyrrole particles. The scaffolds did not possess cytotoxicity and allowed cell adhesion and growth on the surface. Using the in vivo-mimicking conditions in a bioreactor, cells were also able to grow into the structure of the scaffolds. The technique of scaffold preparation used here thus overcomes the limitations of conductive polymers (e.g. poor solubility in an aqueous environment, and limited miscibility with other hydrophilic polymer matrices) and moreover leads to the preparation of cytocompatible scaffolds with potentially cell-instructive properties, which may be of advantage in the healing of damaged electro-sensitive tissues.
Polyaniline cryogel is a new unique form of polyaniline combining intrinsic electrical conductivity and the material properties of hydrogels. It is prepared by the polymerization of aniline in frozen poly(vinyl alcohol) solutions. The biocompatibility of macroporous polyaniline cryogel was demonstrated by testing its cytotoxicity on mouse embryonic fibroblasts and via the test of embryotoxicity based on the formation of beating foci within spontaneous differentiating embryonic stem cells. Good biocompatibility was related to low contents of low-molecular-weight impurities in polyaniline cryogel, which was confirmed by liquid chromatography. The adhesion and growth of embryonic stem cells, embryoid bodies, cardiomyocytes, and neural progenitors prove that polyaniline cryogel has the potential to be used as a carrier for cells in tissue engineering or bio-sensing. The surface energy as well as the elasticity and porosity of cryogel mimic tissue properties. Polyaniline cryogel can therefore be applied in bio-sensing or regenerative medicine in general, and mainly in the tissue engineering of electrically excitable tissues.
- MeSH
- algoritmy MeSH
- aniliny chemie MeSH
- biokompatibilní materiály chemie MeSH
- buněčné kultury MeSH
- elektrická vodivost MeSH
- fibroblasty MeSH
- kryogely chemie MeSH
- mechanické jevy MeSH
- modul pružnosti MeSH
- myši MeSH
- poréznost MeSH
- teoretické modely MeSH
- testování materiálů MeSH
- tkáňové inženýrství MeSH
- viabilita buněk MeSH
- vysokoúčinná kapalinová chromatografie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Conducting polyaniline can be prepared and modified using several procedures, all of which can significantly influence its applicability in different fields of biomedicine or biotechnology. The modifications of surface properties are crucial with respect to the possible applications of this polymer in tissue engineering or as biosensors. Innovative technique for preparing polyaniline films via in-situ polymerization in colloidal dispersion mode using four stabilizers (poly-N-vinylpyrrolidone; sodium dodecylsulfate; Tween 20 and Pluronic F108) was developed. The surface energy, conductivity, spectroscopic features, and cell compatibility of thin polyaniline films were determined using contact-angle measurement, the van der Pauw method, Fourier-transform infrared spectroscopy, and assay conducted on mouse fibroblasts, respectively. The stabilizers significantly influenced not only the surface and electrical properties of the films but also their cell compatibility. Sodium dodecylsulfate seems preferentially to combine both the high conductivity and good cell compatibility. Moreover, the films with sodium dodecylsulfate were non-irritant for skin, which was confirmed by their in-vitro exposure to the 3D-reconstructed human tissue model.
- MeSH
- aniliny škodlivé účinky chemie MeSH
- fibroblasty účinky léků MeSH
- koloidy škodlivé účinky chemie MeSH
- membrány umělé * MeSH
- myši MeSH
- spektroskopie infračervená s Fourierovou transformací MeSH
- viabilita buněk účinky léků MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Polyaniline shows great potential and promises wide application in the biomedical field thanks to its intrinsic conductivity and material properties, which closely resemble natural tissues. Surface properties are crucial, as these predetermine any interaction with biological fluids, proteins and cells. An advantage of polyaniline is the simple modification of its surface, e.g., by using various dopant acids. An investigation was made into the adhesion, proliferation and migration of mouse embryonic fibroblasts on pristine polyaniline films and films doped with sulfamic and phosphotungstic acids. In addition, polyaniline films supplemented with poly (2-acrylamido-2-methyl-1-propanesulfonic) acid at various ratios were tested. Results showed that the NIH/3T3 cell line was able to adhere, proliferate and migrate on the pristine polyaniline films as well as those films doped with sulfamic and phosphotungstic acids; thus, utilization of said forms in biomedicine appears promising. Nevertheless, incorporating poly (2-acrylamido-2-methyl-1-propanesulfonic) acid altered the surface properties of the polyaniline films and significantly affected cell behavior. In order to reveal the crucial factor influencing the surface/cell interaction, cell behavior is discussed in the context of the surface energy of individual samples. It was clearly demonstrated that the lesser the difference between the surface energy of the sample and cell, the more cyto-compatible the surface is.
- MeSH
- aniliny chemie farmakologie MeSH
- biokompatibilní materiály chemie farmakologie MeSH
- buněčná adheze účinky léků MeSH
- buňky NIH 3T3 MeSH
- myši MeSH
- pohyb buněk účinky léků MeSH
- povrchové vlastnosti MeSH
- proliferace buněk účinky léků MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
UNLABELLED: FerB is a flavin mononucleotide (FMN)-containing NAD(P)H: acceptor oxidoreductase of unknown function that is found in the cytoplasm of the bacterium Paracoccus denitrificans. Based on measurements of fluorescence anisotropy, we report here that recombinant FerB readily binds to artificial membrane vesicles. If ubiquinone is incorporated into the membrane, FerB catalyzes its conversion to ubihydroquinone, which may be followed fluorimetrically (with ferricyanide and pyranine entrapped inside the liposomes) or by HPLC. FerB also reduces exogenously added superoxide or superoxide that has been enzymatically generated by the xanthine/xanthine oxidase system or P. denitrificans membrane vesicles. In whole cells, deficiency of FerB increases sensitivity to methyl viologen, as indicated by a lower growth rate and increased production of reactive aldehydes (by-products of lipid oxidation). Taken together, these data support a role for FerB in protection of cells against lipid peroxidation-mediated oxidative stress, and suggest that FerB is a prokaryotic counterpart of mammalian NAD(P)H: quinone oxidoreductase 1.
- MeSH
- antioxidancia chemie metabolismus MeSH
- flavoproteiny chemie metabolismus MeSH
- kinetika MeSH
- membránové proteiny chemie metabolismus MeSH
- oxidace-redukce MeSH
- oxidační stres * MeSH
- Paracoccus denitrificans enzymologie MeSH
- superoxidy metabolismus MeSH
- ubichinon metabolismus MeSH
- xanthin metabolismus MeSH
- xanthinoxidasa metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
