Hemocompatibility and swelling studies of poly(2-hydroxyethyl methacrylate-co-itaconic acid-co-poly(ethylene glycol) dimethacrylate) hydrogels

Abstract

In this study a novel series of hydrogels, based on 2-hydroxyethyl methacrylate (HEMA), itaconic acid (IA) and poly(ethylene glycol) dimethacrylates (PEGDMA) (of varying molecular weight and concentration) were prepared by free radical cross-linking copolymerization. Preliminary hemocompatibility characterization of hydrogels obtained by hemolytic activity assay indicated good compatibility with blood. Preliminary biocompatibility characterization of P(HEMA/IA/PEGDMA) hydrogels, done by the cytotoxicity assays using the HeLa cell line revealed that the cell viability of all samples was in the range of 97-100%, with no significant decrease in cell viability with the change of PEGDMA molecular weight and concentration. Swelling studies were conducted for all P(HEMA/IA/PEGDMA) samples in a physiological pH and temperature range and network parameters were determined. Swelling studies showed pH sensitive behaviour, typical for anionic hydrogels, and temperature dependent swelling. The effects of concentration of PEGDMA component on hydrogel swelling properties depend on the PEGDMA molecular weight. The samples with 550PEGDMA show different swelling capacities when 550PEGDMA content is changed, whereas for P(HEMA/IA/875PEGDMA) samples there was practically no difference in equilibrium degree of swelling, qe, with varying 875PEGDMA content, which trend is the same as in the case of qe versus pH dependences. It was concluded that P(HEMA/IA/PEGDMA) hydrogels show good potential to be used as biomedical materials.

U radu je izvedena sinteza dva nova tipa kopolimernih hidrogelova na bazi 2- -hidroksietil (met)akrilata, itakonske kiseline i poli(etilen glikol) dimetakrilata, s ciljem primene ovih polimernih sistema u biomedicinske svrhe. Testirana je biokompatibilnost preko probe hemokompatibilnosti. Hemolitička aktivnost svih hidrogelova je bila u dozvoljenim granicama, prihvatljivim za biomedicinsku primenu. Studije bubrenja hidrogelova, izvedene u opsegu fizioloških pH i temperaturnih vrednosti, pokazale su da bubrenje zavisi od pH i temperature. Sintetisani hidrogelovi su pokazali sličan trend zavisnosti stepena bubrenja od pH i temperature. Sadržaj 550PEGDMA u hidrogelu utiče na stepen bubrenja, dok koncentracija 875PEGDMA komponente vrlo malo utiče na stepen bubrenja. Hidrogel sa 15 mol% 550PEGDMA manje bubri od uzoraka sa manjim sadržajem ove komponente (5 i 10 mol%), što ukazuje da pri toj koncentraciji preovladava umrežavajuće dejstvo ove komponente. Duži PEG lanci u 875PEGDMA su fleksibilniji, pa je efekat umrežavanja uravnotežen sa efektom fleksibilnosti lanca, što ima za posledicu slično bubrenje za sve uzorke u opsegu koncentracija koje su korišćene u ovom radu.