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Adhesion and growth of human osteoblast-like cells on aliphatic polyesters with different chemical composition, surface roughness and modification with hydroxyapatite

Vagaska B., Bacakova L., Pamuła E., Lisa V., Dobrzyński P.

Inżynieria Biomateriałów

2006

R. 9, nr 58-60

4-7

In this study we have investigated the effect of three groups of polymeric foils on the behavior of MG 63 osteoblast-like cells. These included (1) poly(L-lactide) (PLLA) compared with newly synthesized copolymer of L-lactide and trimethylene carbonate (PLTMC 50:50), (2) three samples made of glycolide and epsylon-caprolactone copolymer (PGCap) with different surface roughness and topography, and finally (3) copolymer of glycolide with L-lactide (PGLA) compared with its modification with hyroxyapatite deposits. On the 1st and 4th day of cultivation the cell number on all of the samples was lower than on control polystyrene culture dish. However, on day 8 after seeding, the values on the tested samples caught up with the control polystyrene. In the first group the cell number of PLTMC was higher than on polystyrene or PLLA. In the second group, the number of cells on PGCap samples of the lower surface roughness (RRMS 130 and 180 nm) was significantly higher than that on the control polystyrene, whereas on the PGCap samples with the rounghness in micrometers, it was comparable to the value on the polystyrene. Moreover, the surface roughness influenced the cell adhesion area. The cells on the sample with the highest roughness index were roundly shaped and their adhesion area was significantly lower, because the cells were restricted in their spreading by the surface structure of the material. In the last group, the number of cells on day 8 on the polymer with hydroxyapatite deposits was significantly higher than on standard tissue culture polystyrene dish, as well as on unmodified PGLA foil, which suggested that hydroxyapatite supports cell proliferation.

Degradowalne poli(estrouretany) z cykloalifatycznego diizocyjanianu i kopoliestrodioli z L-laktydu i poli (epsilon-kaprolaktono) diolu

Masiulanis B., Radomska A., Żegliński J.

Elastomery

2003

T. 7, nr 4

3-9

Opisano syntezę liniowych poli(estrouretanów) (PESU) z 4,4`-diizocyjanianu dicykloheksylenometanu, 1,4 - butanodiolu i kopoliestrodioli z L-laktydu (LA) i poli(e-kaprolaktono)diolu (PCL, Mn 560 g/mol). Kopoliestrodiole o Mn 760, 1250 i 3390 g/mol otrzymano przy trzech stosunkach masowych PLA i PCL w obecności oktanianu Sn (II). PESU otrzymane przy różnych stosunkach molowych komponentów scharakteryzowano przez pomiary twardości, wytrzymałości na rozciąganie i badania degradowalności w buforze fosforanowym o pH = 7,4, w temp. 38 0C. Oznaczono kąty zwilżania wodą, chłonność wody i chłonność oleju roślinnego. Właściwości termiczne PESU określono z użyciem dynamiczno-mechanicznej analizy termicznej (DMTA) i analizy termograwimetrycznej (TGA). Podatność otrzymanych PESU na degradację hydrolityczną porównano z degradowalnością opisanych w literaturze usieciowanych poli(estrouretanów) opartych na kopoliestrotriolach z LA i epsilon-kaprolaktonu.

Synthesis of the linear poly(esterurethanes) (PESUs) from the cycloaliphatic diisocyanate, 1,4-butane diol and copolyesterdiols from L-lactide (LA) and poly(e-caprolactone) diol (PCL, Mn 560 g/mol) have been described. The copolyester diols of Mn 760, 1250 and 3390 g/mol were prepared with three mass proportion of LA and PCL in the presence of Sn (II) octoate. PESUs obtained with different molar ratio of the components were characterized by hardness, tensile-stress properties and degradability in the phosphate buffer solution of pH = 7,4 at temp. 38 0C. The contact angles with water, sorption of water and vegetable oil were denoted. Thermal properties of PESUs were investigated by dynamic mechanical thermal analysis (DMTA) and by thermogravimetric analysis (TGA). The fitness of PESUs on hydrolytical degradability has been compared with degradability of known crosslinked poly(esterurethanes) from copolyester triols based on LA and epsilon-caprolactone.

Mechanism of dispersion polymerization of L-lactide initiated with 2,2-dibutyl-2-stanna-1,3-dioxepane

Sosnowski S., Słomkowski S., Lorenc A., Kricheldorf H.

Zeszyty Naukowe. Chemia / Politechnika Śląska

1999

z. 140

97-100

Biodegradable polyester microspheres were synthesized directly from L-lactide by ring opening polymerization initiated with 2,2-dibutyl-2-stanna-1,3-dioxepane. The polymerization was conducted in dispersion in mixture of organic solvents (heptane/dioxane 4:1 v:v) at 95 degrees centigrade. Cyclic oligomers of L-lactide were detected for the first time in synthesized polymer using MALDI-TOF spectroscopy, indicating presence of intra- and inter- transesterification reactions.

Biodegradowalne mikrosfery poliestrowe syntezowano bezpośrednio z L-laktydu na drodze polimeryzacji z otwarciem pierścienia inicjowanej 2,2-dibutylo-2-stanna-1,3-dioksepanem. Polimeryzacja była prowadzona w dyspersji w mieszaninie rozpuszczalników organicznych (heptan/dioksan objętościowo 4:1) w 95 stopni C. Obserwowana po raz pierwszy za pomocą techniki MALDI-TOF obecność cyklicznych oligomerów L-laktydu w syntetyzowanym polimerze świadczy o występowaniu reakcji inter i intratransestryfikacji.