Plasma modification
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Plasma discharge was used to modify the ETFE surface properties. The changes induced by various plasma power and exposure time were determined by goniometry, gravimetric analysis and atomic force microscopy. It was found that a significant decrease of contact angle after plasma exposure is connected with the surface oxygen increase. Plasma treatment also induced a significant ablation of ETFE and fragmentation of its lamellar structure. The disruption of the lamellar structure was more pronounced for higher plasma power. It was found that by varying plasma power and exposure time it is possible to induce selective surface changes which can subsequently be used for various tissue engineering applications.
It may be possible to regulate the cell colonization of biodegradable polymer nanofibrous membranes by plasma treatment and by the density of the fibers. To test this hypothesis, nanofibrous membranes of different fiber densities were treated by oxygen plasma with a range of plasma power and exposure times. Scanning electron microscopy and mechanical tests showed significant modification of nanofibers after plasma treatment. The intensity of the fiber modification increased with plasma power and exposure time. The exposure time seemed to have a stronger effect on modifying the fiber. The mechanical behavior of the membranes was influenced by the plasma treatment, the fiber density, and their dry or wet state. Plasma treatment increased the membrane stiffness; however, the membranes became more brittle. Wet membranes displayed significantly lower stiffness than dry membranes. X-ray photoelectron spectroscopy (XPS) analysis showed a slight increase in oxygen-containing groups on the membrane surface after plasma treatment. Plasma treatment enhanced the adhesion and growth of HaCaT keratinocytes on nanofibrous membranes. The cells adhered and grew preferentially on membranes of lower fiber densities, probably due to the larger area of void spaces between the fibers.
- MeSH
- buněčná adheze fyziologie MeSH
- buněčné linie MeSH
- keratinocyty cytologie fyziologie MeSH
- lidé MeSH
- membrány umělé * MeSH
- nanovlákna chemie ultrastruktura MeSH
- obvazy MeSH
- pevnost v tahu MeSH
- pevnost v tlaku MeSH
- plazmové plyny chemie MeSH
- pokovování galvanické MeSH
- povrchové vlastnosti MeSH
- proliferace buněk fyziologie MeSH
- testování materiálů MeSH
- tvrdost MeSH
- umělá kůže * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Cellulose-based biomaterials are safe and ordinarily used in human medicine. Owing to its properties, cellulose is still in the biomaterial research spotlight, mainly in wound dressing area. The review brings an overview of chemical and physical means of cellulose modification that have been done so far, particularly to improve material properties and to introduce antibacterial properties. The most frequent antibacterial finishing of cellulose-based materials is the modification with silver that is effective against broad spectrum of bacteria species and has low risk of resistance development. A special subchapter is therefore dedicated to the antibacterial effect of silver.
- Klíčová slova
- fyzikální modifikace, chemická modifikace,
- MeSH
- antibakteriální látky klasifikace terapeutické užití MeSH
- biokompatibilní materiály * klasifikace MeSH
- celulosa * analogy a deriváty chemie klasifikace MeSH
- lidé MeSH
- oxidace-redukce MeSH
- plazmové plyny klasifikace MeSH
- rány a poranění ošetřování MeSH
- regenerativní lékařství MeSH
- sloučeniny stříbra terapeutické užití MeSH
- stříbro terapeutické užití MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
Regardless of the route of administration, some or all of a therapeutic agent will appear in the blood stream, where it can act on blood cells and other components of the plasma. Recently we have shown that poly(ethylene imines) (PEIs) which interact with plasma proteins are taken up into erythrocyte membranes. These observations led us to investigate the interactions between maltose functionalized hyperbranched PEIs (PEI-Mal) and plasma proteins. Two model proteins were chosen - human serum albumin (HSA) (albumins constitute ∼60% of all plasma proteins), and lysozyme. HSA is a negatively charged 66kDa protein at neutral pH, whereas lysozyme is a positively charged 14kDa protein. Fluorescence quenching and changes in the conformation of the amino acid tryptophan, diameter and zeta potential of proteins were investigated to evaluate the interaction of PEI-Mal with proteins. PEI-Mal interacts with both types of proteins. The strength of dendritic glycopolymer interactions was generally weak, especially with lysozyme. Greater changes were found with HSA, mainly triggered by hydrogen bonds and the electrostatic interaction properties of dendritic glycopolymers. Moreover, the structure and the size of PEI-Mal macromolecules affected these interactions; larger macromolecules with more sugar groups (95% maltose units) interacted more strongly with proteins than smaller ones with lower sugar modification (33% maltose units). Due to (i) the proven overall low toxicity of sugar-modified PEIs and, (ii) their ability to interact preferentially through hydrogen bonds with proteins of human plasma or possibly with other interesting protein targets, PEI-Mal is a good candidate for creating therapeutic nanoparticles in the fast developing field of nanomedicine.
- MeSH
- dendrimery chemie MeSH
- fluorescence MeSH
- iminy chemie MeSH
- krevní proteiny chemie MeSH
- lidé MeSH
- maltosa chemie MeSH
- muramidasa chemie MeSH
- polyethyleny chemie MeSH
- polymery chemie MeSH
- sérový albumin chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Regeneration of large bone defects caused by trauma or tumor resection remains one of the biggest challenges in orthopedic surgery. Because of the limited availability of autograft material, the use of artificial bone is prevalent; however, the primary role of currently available artificial bone is restricted to acting as a bone graft extender owing to the lack of osteogenic ability. To explore whether surface modification might enhance artificial bone functionality, in this study we applied low-pressure plasma technology as next-generation surface treatment and processing strategy to chemically (amine) modify the surface of beta-tricalcium phosphate (β-TCP) artificial bone using a CH4/N2/He gas mixture. Plasma-treated β-TCP exhibited significantly enhanced hydrophilicity, facilitating the deep infiltration of cells into interconnected porous β-TCP. Additionally, cell adhesion and osteogenic differentiation on the plasma-treated artificial bone surfaces were also enhanced. Furthermore, in a rat calvarial defect model, the plasma treatment afforded high bone regeneration capacity. Together, these results suggest that amine modification of artificial bone by plasma technology can provide a high osteogenic ability and represents a promising strategy for resolving current clinical limitations regarding the use of artificial bone.
- MeSH
- biokompatibilní materiály metabolismus MeSH
- buněčná diferenciace fyziologie MeSH
- fosforečnany vápenaté metabolismus MeSH
- kostní náhrady metabolismus terapeutické užití MeSH
- krysa rodu rattus MeSH
- osteogeneze fyziologie MeSH
- regenerace kostí fyziologie MeSH
- transplantace kostí metody MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem 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
