Fogorvosi szemle, 2007 (100. évfolyam, 1-6. szám)

2007-02-01 / 1. szám

31 FOGORVOSI SZEMLE ■ 100. évf. 1. sz. 2007. hatására bennük nagyobb, gyakran repedéshez, tö­réshez vezető feszültség keletkezik. Eredményeink alapján megállapíthatjuk, hogy a fotopolimerizációval előállított hidrogélek térhálósűrűsége jellemzően meg­határozza a nyomószilárdságot és az ezzel összefüg­gésben lévő fizikai paramétereket (pl.: nyomási, illetve rugalmassági modulus), vagyis az összetevők változ­tatásával befolyásolható fizikai paraméterekkel rendel­kező anyagot hoztunk létre. Köszönetnyilvánítás A kutatás a RET (Regionális Egyetemi Tudásközpont) kapcsolódási szám (RET-06/432/2004) és (RET-06/ 423/2004) támogatásával valósult meg. Köszönettel tartozunk még Rózsáné Lukács Júlia méréseinkben nyújtott segítségéért. (Alkalmazott Kémiai Tanszék, Dr. Zsuga Miklós tanszékvezető egyetemi tanár, Dr. Deák György tudományos munkatárs) Irodalom 1. Bako J, Szepesi M, Veres AJ, Borbély ZsM, Hegedűs Cs, Borbély J: Chlorhexidine release from nanocomposit hydrogels. Polym Mat Sci & Eng 2006; 94: 367-368. 2. CoviELLO T, Alhaique F, Párisi O, Matricardi P, Bocchinfuso G, Grassi M: A new polysaccharidic gel matrix for drug delivery: prepa­ration and mechanical properties. J Control Release_2005; 102(3): 643-656. 3. Das A, Wadhwa S, Srivastava AK: Cross-linked guar gum hydro­gel discs for colon-specific delivery of ibuprofen: formulation and in vitro evaluation. Drug Deliv2006; 13(2): 139-142. 4. Einerson NJ, Stevens KR, Kao WJ: Synthesis and physicochemi­cal analysis of gelatin-based hydrogels for drug carrier matrices. Bi­omaterials 2002; 24: 509-523. 5. Hsiue G-H, Guu J-A, Cheng C-C: Poly(2-hydroxyethyl methacrylate) film as a drug delivery system for pilocarpine. Biomaterials 2001 ; 22: 1763-1769. 6. Gispets J, Sola R, Varon C: The influence of water content of hy­drogel contact lenses when fitting patients with .tear film deficiency1. Cont Lens Anterior Eye 2000; 23(1 ): 16-21. 7. Gyenes T, Zrínyi M: Szabályozott hatóanyag-leadó rendszerek. Paradigmaváltás a gyógyszerészetben. Acta Pharm Hung 2001; 71(4): 405-421. 8. Jankunas V, Rimdeika R, Pilipaityte L: Treatment of the leg ulcers by skin grafting. Medicina (Kaunas) 2004; 40(5): 429-433. 9. Johnson B, Niedermaier DJ, Crone WC, Moorthy J, Beebe DJ: Me­chanical properties of a pH sensitive hydrogel. Society for Experi­mental Mechanics, SEM Annual Conference Proceedings, Milwau­kee, Wl, 2002. 10. Kim JJ, Park K: Modulated insulin delivery from glucose-sensi­tive hydrogel dosage forms. J Controlled Release 2001; 77(1): 39- 47. 11. Li H, Yew YK, Lam KY, Ng TY: Numerical simulation of pH-stim­­uli responsive hydrogel in buffer solutions. Colloid Surface 2004; 49(1-3): 149-154. 12. Nuno-Donlucas SM, Sàncez-Dîaz JC, Rabelero M, Cortés-Orte­­ga J, Lurhs-Olmos CC, Fernández-Escamilla VV, Mendizábal E, Puig JE: Microstructured polyacrylamide hydrogels made with hydropho­bic nanoparticles. J Colloid Interface Sei 2004; 270(1 ): 94-98. 13. Sakkers RJB, Dalmeyer RAJ, Jr De Wijn, Van Blitterswijk CA: Use of bone-bonding hydrogel copolymers in bone: An in vitro and in vivo study of expanding PEO-PBT copolymers in goat femora. J Biomed Mater Res 2000; 49(3): 312-318. 14. Szántó F: A kolloidkémia alapjai. JATEPRess, Szeged, 1995; 289-305. 15. Van Dijkhuizen-Radersma R, Métairie S, Roosma JR, De Groot K, Bezeimer JM: Controlled release of proteins from degradable poli(ether-ester) multiblock copolymers. J Control Release 2005; 101(1-3): 175-186. Dr. Szepesi M, Bakó J, Márton S, Dr. Borbély J, Dr. Hegedűs Cs: Synthesis and compression strength of hydrogels The purpose of the present investigation was the synthesis of crosslinked polymers and the assay of the effect of the monomer ratio to the compression values. Hydrogels were made by free radical photoinitiation from 2-hydroxyethyl metachrylate (HEMA) monomer, polyethylene glycol) dimethacrylate (PEG-DMA) crosslinker and sodium anthraqui­­none-2-sulphonate initiation The concentration of HEMA and PEG-DMA was 30 %, and their ratio was varied to obtain gels with different crosslinking density. It was found, that increasing the amount of the crosslinker in the gels, the force of the deformation increased, howev­er the elasticity decreased. The lowest difference was found between the molar ratio of 50% HEMA: 50% PEG-DMA and the 75% HEMA: 25% PEG-DMA gels. Compression strength was strongly influenced on the ratio of the crosslink­ing agent. The smallest compression strength was found at the lowest amount of PEG-DMA (90% HEMA: 10% PEG­­DMA) (0.0475 MPa ± 0.0117) and the highest value was found at the highest amount of the PEG-DMA (10% HEMA: 90% PEG-DMA) (0.1366 MPa ± 0.0546). The values of the compression strength at gels with similar composition was not significantly different. On the base of the present investigations the elasticity of the materials could be calculated from the ratio of mono­mers. It could be an important parameter in the further applications of the gels as a local delivery system in the parod­­ontology. Key words: hydrogel, compression strength, Young-modulus

Next

/
Thumbnails
Contents