surface modification
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Na biomateriály jsou v dnešní době kladeny mnohé požadavky. Jedním z potenciálních biomateriálů nové generace je titan a jeho slitiny s nanotubulární povrchovou úpravou, kterou lze připravit poměrně levně a jednoduše metodou anodické oxidace za vhodných podmínek. Tato nanostruktura má osteoinduktivní a osteokonduktivní vlastnosti. Výběr nejvhodnější geometrie a přesný mechanismus působení teprve čeká na objasnění.
Biomaterials nowadays should meet various criteria. One of the promising biomaterials of the new generation is titanium and its alloys with a nanotubular surface modification prepared by anodic oxidation at appropriate conditions. This relatively inexpensive and simple method leads to the nanostructure with osteoinductive and osteoconductive properties. Selection of the most suitable geometry and exact mechanism of action has to be elucidated.
- MeSH
- biokompatibilní materiály MeSH
- biologické modely MeSH
- biomedicínské inženýrství MeSH
- buněčné linie MeSH
- extracelulární matrix MeSH
- fyziologie buňky účinky léků MeSH
- kosti a kostní tkáň * účinky léků MeSH
- krysa rodu rattus MeSH
- lidé MeSH
- mezenchymální kmenové buňky MeSH
- modely u zvířat MeSH
- myši MeSH
- nanostruktury MeSH
- nanotechnologie MeSH
- osteoblasty MeSH
- slitiny MeSH
- techniky in vitro MeSH
- titan * chemie MeSH
- výzkum MeSH
- Check Tag
- krysa rodu rattus MeSH
- lidé MeSH
- myši MeSH
The increase in surface Gibbs energy of polypropylene (PP) by cold barrier plasma is a promising alternative to chemical modification. The advantage of using this discharge method compared with other types such as corona or glow discharge, consists in a better process control by homogenous plasma formation and in an efficient deposition of thin layers. As a result of the reactive site formation by plasma treatment, it is possible to initiate graft radical polymerization of acrylic acid, acrylamide or methyl methacrylate on PP surface, which leads to films with new physico-chemical properties such as morphology, thickness, polarity, and surface chemical composition. On the films thus formed it is possible to efficiently immobilize antibacterial polysaccharides, such as chitosan, pectin and cyclodextrin copolymers, which increase the PP biocompatibility by reducing the biofilm formation. This method can be used in food and textile industries, biomedicine and in production of new composites and nanocomposites.
- MeSH
- antibakteriální látky * chemie MeSH
- biomedicínský výzkum MeSH
- chemické jevy MeSH
- chitosan chemie MeSH
- lidé MeSH
- polypropyleny * chemie MeSH
- protézy a implantáty využití MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- MeSH
- barvicí látky chemie terapeutické užití MeSH
- citlivost dentinu etiologie terapie MeSH
- dentin chemie účinky záření ultrastruktura MeSH
- erythrosin MeSH
- extrakce zubů MeSH
- finanční podpora výzkumu jako téma MeSH
- laserová koagulace metody využití MeSH
- laserová terapie MeSH
- lasery MeSH
- lidé MeSH
- molár třetí účinky záření MeSH
- Check Tag
- lidé MeSH
Cíl: pomocí pokusů in vitro studovat vliv povrchových vlastností vybraných implantačních materiálů na adherenci některých krevních složek (plazma, sérum) a sledovat vliv těchto adsorbovaných proteinů na povrchu implantátu na adhezi i syntetickou aktivitu kultivovaných osteoblastů. Metodika: U zvolených materiálů : titan leptaný (Ti-Etch), titan plazma-sprayovaný (Ti-PlaSpray), titan s hydroxyapatitovou vrstvou (Ti-HA), a uhlíkový kompozit (C/C) byly stanoveny fyzikálně-chemické parametry povrchu (drsnost, smáčivost a volná povrchová energie). Jako kontrola sloužil polystyren kultivačních destiček pro tkáňové kultury (TCPS). Biologická úprava materiálů byla provedena pokrytím jednou ze dvou vybraných krevních komponent–plazma nebo sérum. Na materiálech bez pokrytí i s biologickou úpravou byly kultivovány osteoblasty a následně byla z mitochondriální oxidační aktivity monolayeru buněk (MTT test) vyhodnocena jejich proliferace. V získaném kultivačním médiu byla pomocí enzymoimunosorbentní analýzy (ELISA) stanovena aktivita osteoblastů jako hladina kostní alkalické fosfatázy (BAP) a produkce zánětlivých cytokinů (TNF-?, IL-8). Výsledky: Vysoká drsnost implantátů ovlivnila zvýšenou proliferaci u titanových materiálů (Ti-PlaSpray). Nízká proliferace C/C je přičítána téměř nulové hodnotě polární složky povrchové energie. Potažení materiálů aktivovanou plazmou (fibrinovou sítí) vedlo ke vzniku unifikovaného povrchu jak z hlediska proliferace, tak i z hlediska syntetické aktivity. Oproti tomu při potažení implantátů sérem (albuminem) nebyl pozorován takový stimulační efekt na osteoblasty jaký jsme předpokládali. Závěr: Pokrytí vybraných implantačních materiálů aktivovanou plazmou (tj. fibrinovou sítí) vede k vytvoření povrchu s potřebnou rovnováhou mezi mírou proliferace a syntetickou aktivitou osteoblastů jako modelu imunitní odpovědi organizmu na zavedený implantát.
Aim of the study: To study the impact of surface properties of selected implant materials on adherence of some blood components (plasma, serum), and the impact of these proteins, adsorbed on the implant surface, on the adhesion and synthetic activity of cultured osteoblasts using in vitro experiments. Methods: In selected materials such as etched titanium (Ti-Etch), plasma-sprayed titanium (Ti-PlaSpray), titanium with hydroxyapatite layer (Ti-HA), and carbon composite (C/C), the physiochemical parameters were determined (roughness, wettability, and free surface energy). Tissue culture polystyrene (TCPS) was used as a control. Biological modification of materials was performed by overlaying of one of two selected blood components – plasma or serum. Osteoblasts were cultured on materials without overlay, as well as materials with biological modification, and consequently, the proliferation of osteoblasts was evaluated due to the mitochondrial oxidation activity of monolayer (MTT assay). In the obtained culture medium, the activity of osteoblasts was determined as the level of bone alkaline phosphatase (BAP) and the production of inflammatory cytokines (TNF-?, IL-8) using enzyme-linked immunosorbent assay (ELISA). Results: High roughness of implants affected the increased proliferation in titanium materials (Ti-PlaSpray). A decreased proliferation of C/C is attributed to almost zero value of polar component of surface energy. Overlaying of materials by activated plasma (fibrin network) led to formation of unified surface in terms of both proliferation and synthetic activity. However, overlaying of implants by serum (albumin) did not have the anticipated stimulatory effect on osteoblasts. Conclusion: Overalying of selected implant materials by activated plasma (i.e. fibrin network) leads to formation of a surface with required balance between the proliferation rate and synthetic activity of osteoblasts as a model of organisms’s immune response to an applied implant. Key words:
- MeSH
- adhezivita MeSH
- cytokiny imunologie MeSH
- ELISA metody využití MeSH
- financování organizované MeSH
- krevní buňky metabolismus MeSH
- krevní plazma fyziologie metabolismus MeSH
- lidé MeSH
- osteoblasty metabolismus MeSH
- povrchové napětí MeSH
- povrchové vlastnosti MeSH
- proliferace buněk MeSH
- protézy a implantáty škodlivé účinky MeSH
- sérum fyziologie metabolismus MeSH
- smáčivost MeSH
- Check Tag
- lidé 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
Liposomes are one of the most important drug delivery vectors, nowadays used in clinics. In general, polyethylene glycol (PEG) is used to ensure the stealth properties of the liposomes. Here, we have employed hydrophilic, biocompatible and highly non-fouling N-(2-hydroxypropyl) methacrylamide (HPMA)-based copolymers containing hydrophobic cholesterol anchors for the surface modification of liposomes, which were prepared by the method of lipid film hydration and extrusion through 100 nm polycarbonate filters. Efficient surface modification of liposomes was confirmed by transmission electron microscopy, atomic force microscopy, and gradient ultracentrifugation. The ability of long-term circulation in the vascular bed was demonstrated in rabbits after i.v. application of fluorescently labelled liposomes. Compared to PEGylated liposomes, HPMA-based copolymer-modified liposomes did not induce specific antibody formation and did not activate murine and human complement. Compared with PEGylated liposomes, HPMA-based copolymer-modified liposomes showed a better long-circulating effect after repeated administration. HPMA-based copolymer-modified liposomes thus represent suitable new candidates for a generation of safer and improved liposomal drug delivery platforms.
- MeSH
- akrylamidy chemie MeSH
- aktivace komplementu účinky léků MeSH
- cholesterol chemie krev MeSH
- hydrofobní a hydrofilní interakce * MeSH
- králíci MeSH
- lékové transportní systémy MeSH
- lidé MeSH
- liposomy * MeSH
- myši MeSH
- polyethylenglykoly * chemie MeSH
- polymery chemie MeSH
- povrchové vlastnosti * MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Carbon quantum dots (CQDs) have great potential to be utilized as an optical sensing probe due to its unique photoluminescence and less toxic properties. This work reports a simple and novel synthesis method of carbon dots via direct acid hydrolysis in presence of polyethylene glycol (PEG), polyvinylpyrrolidone (PVP) and bovine serum albumin protein (BSA). In this study, fluorescent CQDs were synthesized by using citric acid and ascorbic acid as the source of carbon precursors, which was covered with polyethylene glycol (PEG), polyvinylpyrrolidone (PVP) and with bovine serum albumin (BSA), by microwave irradiation. Furthermore, the synthesis parameters as power, reaction time and temperature were studied and quality of prepared CQDs were investigated by spectral methods. Short reaction time (20 min) and temperature from 120 ºC to 140 ºC under microwave irradiation are sufficient to prepare luminescence carbon quantum dots. Absorption spectra and photoluminescence spectra were measured to characterize prepared dots in water solution. The photoluminescence spectra of CQDs doped with different protection compound show the different luminescent and excitation wavelengths starting from 330 nm to 430 nm. Importantly, these CQDs are demonstrated to be excellent bioimaging agents and fluorescent ink due to their stable emission, well dispersibility, low toxicity, long emission life time, and good compatibility with different macromolecules.
- MeSH
- fluorescence MeSH
- kvantové tečky * MeSH
- kyselina askorbová MeSH
- kyselina citronová MeSH
- mikrovlny MeSH
- polyethylenglykoly MeSH
- povidon MeSH
- povrchové vlastnosti * MeSH
- sérový albumin hovězí MeSH
- spektrofotometrie statistika a číselné údaje MeSH
- techniky syntetické chemie MeSH
- teplota MeSH
- uhlík * MeSH
- Publikační typ
- práce podpořená grantem MeSH
- srovnávací studie MeSH