A simple, versatile, protein-repulsive, substrate-independent biomimetic surface modification is presented that is based on the creation of a PEO brush on a polydopamine anchoring layer and its capacity for selective follow-up modifications with various ligands using a copper-catalyzed alkyne-azide cycloaddition reaction. The desired surface concentration of peptide biomimetic ligands can be controlled by adjusting the peptide concentration in the reaction mixture, then measuring the activity of (125)I-radiolabeled peptides that are immobilized on the substrates. The performance of the prepared substrates is tested in cell cultures with MEF cells and a human ECC line.

• MeSH
• biomimetika * MeSH
• cyklizace MeSH
• kultivované buňky MeSH
• lidé MeSH
• povrchové vlastnosti MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

A novel and facile in vitro cell sensing system has been developed with one-step electropolymerization of the conducting polypyrrole(PPy) polymer using RGD peptide as the sole dopant on an indium tin oxide (ITO) surface. The resulted RGD peptide-doped polypyrrole (PPy/RGD) composite film had a robust surface, in which PPy provided a biocompatible matrix for cell growth and a conducting interface for electrical detection, while the RGD peptide entrapped in the PPy matrix conferred the desired biomimetic properties. Using the human lung cancer cell A549 as a model, this system can be used to monitor cell behaviors of proliferation and cytotoxicity.

• Klíčová slova
• RGD peptidy, elektropolymerizace, polypyrrole,
• MeSH
• antitumorózní látky toxicita   MeSH
• biomimetické materiály MeSH
• biosenzitivní techniky * MeSH
• oligopeptidy MeSH
• polymery MeSH
• proliferace buněk MeSH
• pyrroly * MeSH
• skenovací elektrochemická mikroskopie MeSH
• Publikační typ
• práce podpořená grantem MeSH

Protein-repulsive surfaces modified with ligands for cell adhesion receptors have been widely developed for controlling the cell adhesion and growth in tissue engineering. However, the question of matrix production and deposition by cells on these surfaces has rarely been addressed. In this study, protein-repulsive polydopamine-poly(ethylene oxide) (PDA-PEO) surfaces were functionalized with an RGD-containing peptide (RGD), with a collagen-derived peptide binding fibronectin (Col), or by a combination of these peptides (RGD + Col, ratio 1:1) in concentrations of 90 fmol/cm(2) and 700 fmol/cm(2) for each peptide type. When seeded with vascular endothelial CPAE cells, the PDA-PEO surfaces proved to be completely non-adhesive for cells. On surfaces with lower peptide concentrations and from days 1 to 3 after seeding, cell adhesion and growth was restored practically only on the RGD-modified surface. However, from days 3 to 7, cell adhesion and growth was improved on surfaces modified with Col and with RGD + Col. At higher peptide concentrations, the cell adhesion and growth was markedly improved on all peptide-modified surfaces in both culture intervals. However, the collagen-derived peptide did not increase the expression of fibronectin in the cells. The deposition of fibronectin on the material surface was generally very low and similar on all peptide-modified surfaces. Nevertheless, the RGD + Col surfaces exhibited the highest cell adhesion stability under a dynamic load, which correlated with the highest expression of talin and vinculin in the cells on these surfaces. A combination of RGD + Col therefore seems to be the most promising for surface modification of biomaterials, e.g. vascular prostheses.

• MeSH
• adsorpce MeSH
• biomimetika * MeSH
• buněčná adheze * MeSH
• exprese genu MeSH
• fibronektiny chemie   genetika   MeSH
• indoly chemie   MeSH
• kultivované buňky MeSH
• lidé MeSH
• molekulární sekvence - údaje MeSH
• oligopeptidy chemie   MeSH
• polyethylenglykoly chemie   MeSH
• polymery chemie   MeSH
• povrchové vlastnosti MeSH
• sekvence aminokyselin MeSH
• talin genetika   MeSH
• vinkulin genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The design of favorable mechanical properties and suitable surface modifications of hydrogels in order to stimulate specific cell response is a great challenge. N-(2-Hydroxypropyl) methacryl-amide (HPMA) was utilized to form macroporous cryogel scaffolds for stem cell applications. Furthermore, one group of scaffolds was enhanced by copolymerization of HPMA with methacryloyl-GGGRGDS-OH peptide in an effort to integrate biomimetic adhesion sites. The cryogels were characterized by stiffness and equilibrium swelling measurements as well as by scanning electron microscopy. Cell culture experiments were performed with human adipose-derived stem cells and substrates were found completely non-toxic. Moreover, RGDS-enriched cryogels supported cell attachment, spreading and proliferation, so they can be considered suitable for designed aims.

• MeSH
• akrylamidy * MeSH
• biokompatibilní materiály MeSH
• biomimetika * MeSH
• buněčná adheze MeSH
• kmenové buňky * MeSH
• kryogely MeSH
• kultivované buňky MeSH
• lidé MeSH
• poréznost MeSH
• proliferace buněk MeSH
• pružnost MeSH
• tkáňové podpůrné struktury MeSH
• tukové buňky MeSH
• voda chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

In this study a strategy to immobilize phospholipids onto a polymer-based stationary phase is described. Methacrylate-based monoliths in capillary format (150×0.1mm) were modified by soybean phosphatidylcholine through 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide coupling to obtain stationary phases suitable to mimic cell surface membranes. The covalent coupling reaction involves the phosphate group in phospholipids; therefore, the described methodology is suitable for all types of phospholipids. Immobilization of soy bean phosphatidylcholine on the monolith was confirmed by attenuated total reflectance Fourier transform infrared spectroscopy and gas chromatography-mass spectrometry of the fatty alcohol profile, generated upon reductive cleavage of the fatty acyl side chains of the phospholipid on the monolith surface with lithium aluminium hydride. The prepared stationary phases were evaluated through studies on the retention of low-molar mass model analytes including neutral, acidic, and basic compounds. Liquid chromatographic studies confirmed predominant hydrophobic interactions between the analytes and the synthesized stationary phase; however, electrostatic interactions contributed to the retention as well. The synthesized columns showed high stability even with fully aqueous mobile phases such as Dulbecco's phosphate-buffered saline solution.

• MeSH
• biomimetika MeSH
• chemické techniky analytické přístrojové vybavení   metody   MeSH
• chromatografie kapalinová přístrojové vybavení   MeSH
• ethyldimethylaminopropylkarbodiimid chemie   MeSH
• fosfatidylcholiny chemie   MeSH
• fosfolipidy chemie   MeSH
• hydrofobní a hydrofilní interakce MeSH
• methakryláty chemie   MeSH
• polymery chemie   MeSH
• voda chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Composite materials based on a titanium support and a thin, alginate hydrogel could be used in bone tissue engineering as a scaffold material that provides biologically active molecules. The main objective of this contribution is to characterize the activation and the functionalization of titanium surfaces by the covalent immobilization of anchoring layers of self-assembled bisphosphonate neridronate monolayers and polymer films of 3-aminopropyltriethoxysilane and biomimetic poly(dopamine). These were further used to bind a bio-functional alginate coating. The success of the titanium surface activation, anchoring layer formation and alginate immobilization, as well as the stability upon immersion under physiological-like conditions, are demonstrated by different surface sensitive techniques such as spectroscopic ellipsometry, infrared reflection-absorption spectroscopy and X-ray photoelectron spectroscopy. The changes in morphology and the established continuity of the layers are examined by scanning electron microscopy, surface profilometry and atomic force microscopy. The changes in hydrophilicity after each modification step are further examined by contact angle goniometry.

• Publikační typ
• časopisecké články MeSH

Antifouling polymer layers containing extracellular matrix-derived peptide motifs offer promising new options for biomimetic surface engineering. In this contribution, we report the design of antifouling vascular grafts bearing biofunctional peptide motifs for tissue regeneration applications based on hierarchical polymer brushes. Hierarchical diblock poly(methyl ether oligo(ethylene glycol) methacrylate-block-glycidyl methacrylate) brushes bearing azide groups (poly(MeOEGMA-block-GMA-N3)) were grown by surface-initiated atom transfer radical polymerization (SI-ATRP) and functionalized with biomimetic RGD peptide sequences. Varying the conditions of copper-catalyzed alkyne-azide "click" reaction allowed for the immobilization of RGD peptides in a wide surface concentration range. The synthesized hierarchical polymer brushes bearing peptide motifs were characterized in detail using various surface sensitive physicochemical methods. The hierarchical brushes presenting the RGD sequences provided excellent cell adhesion properties and at the same time remained resistant to fouling from blood plasma. The synthesis of anti-fouling hierarchical brushes bearing 1.2 × 103 nmol/cm2 RGD biomimetic sequences has been adapted for the surface modification of commercially available grafts of woven polyethylene terephthalate (PET) fibers. The fiber mesh was endowed with polymerization initiator groups via aminolysis and acylation reactions optimized for the material. The obtained bioactive antifouling vascular grafts promoted the specific adhesion and growth of endothelial cells, thus providing a potential avenue for endothelialization of artificial conduits.

• MeSH
• adsorpce MeSH
• aminokyselinové motivy MeSH
• azidy chemie   MeSH
• biokompatibilní potahované materiály * MeSH
• biomimetické materiály * MeSH
• buněčná adheze MeSH
• buněčné dělení MeSH
• cévní endotel fyziologie   MeSH
• cévní protézy * MeSH
• endoteliální buňky pupečníkové žíly (lidské) MeSH
• imobilizované proteiny MeSH
• křemík MeSH
• krevní plazma MeSH
• krevní proteiny MeSH
• lidé MeSH
• oligopeptidy chemie   MeSH
• polyethylentereftaláty chemie   MeSH
• polymerizace * MeSH
• povrchové vlastnosti MeSH
• řízená tkáňová regenerace přístrojové vybavení   MeSH
• sklo MeSH
• syntetická chemie okamžité shody MeSH
• testování materiálů MeSH
• trombóza prevence a kontrola   MeSH
• zlato MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH

The cell membrane is mainly composed of lipid bilayers with inserted proteins and carbohydrates. Lipid bilayers made of purified or synthetic lipids are widely used for estimating the effect of target compounds on cell membranes. However, the composition of such biomimetic membranes is much simpler than the composition of biological membranes. Interactions between compounds and simple composition biomimetic membranes might not demonstrate the effect of target compounds as precisely as membranes with compositions close to real organisms. Therefore, the aim of our study is to construct biomimetic membrane closely mimicking the state of natural membranes. Liposomes were prepared from lipids extracted from L-α-phosphatidylcholine, Escherichia coli, yeast (Saccharomyces cerevisiae) and bovine liver cells through agitation and sonication. They were immobilized onto silicon dioxide (SiO2) sensor surfaces using N-(2-hydroxyethyl)piperazine-N'-2-ethanesulfonic acid buffer with calcium chloride. The biomimetic membranes were successfully immobilized onto the SiO2 sensor surface and detected by nanoplasmonic sensing. The immobilized membranes were exposed to choline carboxylates. The membrane disruption effect was, as expected, more pronounced with increasing carbohydrate chain length of the carboxylates. The results correlated with the toxicity values determined using Vibrio fischeri bacteria. The yeast extracted lipid membranes had the strongest response to introduction of choline laurate while the bovine liver lipid extracted liposomes were the most sensitive towards the shorter choline carboxylates. This implies that the composition of the cell membrane plays a crucial role upon interaction with choline carboxylates, and underlines the necessity of testing membrane systems of different origin to obtain an overall image of such interactions.

• MeSH
• biomimetické materiály chemie   MeSH
• buněčná membrána chemie   MeSH
• cholin analogy a deriváty   MeSH
• liposomy chemie   MeSH
• membránové lipidy chemie   MeSH
• Saccharomyces cerevisiae MeSH
• skot MeSH
• zvířata MeSH
• Check Tag
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

A pneumatically actuated fluid transporter to transport fluids along surfaces is introduced. The biomimetic approach is based on the transportation principle of fluids by cilia or comb-row arrays due to the generation of metachronal waves. Rows of PDMS flaps which mimic comb-rows are asymmetrically positioned on flexible membranes. Each membrane is deflected by applying a defined pressure profile to achieve a metachronal wave on the surface. The simulations of the membrane behavior as well as a description of the concept by applying metachronal waves to the artificial comb row arrays are presented. The proof-of-concept shows fluid transport of up to 64 µm/s near the flap tips.

• Klíčová slova
• simulace chování membrány, transport částic, transport tekutiny,
• MeSH
• biomimetika * MeSH
• cilie MeSH
• mikrofluidika * MeSH
• Publikační typ
• práce podpořená grantem MeSH

The C-type lectin DC-SIGN expressed on immature dendritic cells is a promising target for antiviral drug development. Previously, we have demonstrated that mono- and divalent C-glycosides based on d-manno and l-fuco configurations are promising DC-SIGN ligands. Here, we described the convergent synthesis of C-glycoside dendrimers decorated with 4, 6, 9, and 12 α-l-fucopyranosyl units and with 9 and 12 α-d-mannopyranosyl units. Their affinity against DC-SIGN was assessed by surface plasmon resonance (SPR) assays. For comparison, parent O-glycosidic dendrimers were synthesized and tested, as well. A clear increase of both affinity and multivalency effect was observed for C-glycomimetics of both types (mannose and fucose). However, when dodecavalent C-glycosidic dendrimers were compared, there was no difference in affinity regarding the sugar unit (l-fuco, IC50 17 μM; d-manno, IC50 12 μM). For the rest of glycodendrimers with l-fucose or d-mannose attached by the O- or C-glycosidic linkage, C-glycosidic dendrimers were significantly more active. These results show that in addition to the expected physiological stability, the biological activity of C-glycoside mimetics is higher in comparison to the corresponding O-glycosides and therefore these glycomimetic multivalent systems represent potentially promising candidates for targeting DC-SIGN.

• MeSH
• biomimetické materiály chemie   farmakologie   MeSH
• fukosa chemie   MeSH
• inhibiční koncentrace 50 MeSH
• lektiny typu C antagonisté a inhibitory   MeSH
• mannosa chemie   MeSH
• molekuly buněčné adheze antagonisté a inhibitory   MeSH
• receptory buněčného povrchu antagonisté a inhibitory   MeSH
• Publikační typ
• časopisecké články MeSH