title: Bioinspired, calcium-free alginate hydrogels with tunable physical and mechanical properties and improved biocompatibility.
abstract: Alginate hydrogels are for various biomedical applications including tissue engineering, cell therapy, and drug delivery. However, it is not easy to control swelling or viscoelastic and biophysical properties of alginate hydrogels prepared by conventional cross-linking methods (ionic interaction using divalent cations). In this study, we describe a bioinspired approach for preparing divalent ion-free alginate hydrogels that exhibit tunable physical and mechanical properties and improved biocompatibility due to the absence of cations in the gel matrices. We conjugated dopamine, a minimalized adhesive motif found in the holdfast pads of mussels, to alginate backbones (alginate-catechol) and the tethered catechols underwent oxidative cross-linking. This resulted in divalent cation-free alginate hydrogels. The swelling ratios and moduli of the alginate-catechol hydrogels are readily tunable, which is difficult to achieve in ionic bond-based alginate hydrogels. Furthermore, alginate-catechol hydrogels enhanced the survival of various human primary cells including stem cells in the three-dimensional gel matrix, indicating that intrinsic cytotoxicity caused by divalent cations becomes negligible when employing catechol oxidation for alginate cross-linking. The inflammatory response in vivo was also significantly attenuated compared to conventional alginate hydrogels with calcium cross-linking. This biomimetic approach for the preparation of alginate hydrogels may provide a novel platform technology to develop tunable, functional, biocompatible, three-dimensional scaffolds for tissue engineering and cell therapy.
authors: Department of Biotechnology, Yonsei University , Seoul 120-749, Republic of Korea.
authors: Changhyun
authors: C
authors: Lee
authors: Jisoo
authors: J
authors: Shin
authors: Jung Seung
authors: JS
authors: Lee
authors: Eunkyoung
authors: E
authors: Byun
authors: Ji Hyun
authors: JH
authors: Ryu
authors: Soong Ho
authors: SH
authors: Um
authors: Dong-Ik
authors: DI
authors: Kim
authors: Haeshin
authors: H
authors: Lee
authors: Seung-Woo
authors: SW
authors: Cho
mesh_terms: D000464:Alginates / Q000737:chemistry*; D000818:Animals; D001672:Biocompatible Materials; D002118:Calcium / Q000737:chemistry*; D002478:Cells, Cultured; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006801:Humans; D020100:Hydrogels; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D008807:Mice, Inbred BALB C; D008855:Microscopy, Electron, Scanning
chemical_list: D000464:Alginates; D001672:Biocompatible Materials; D006603:Hexuronic Acids; D020100:Hydrogels; D020723:Glucuronic Acid; D002118:Calcium