title: A tough, precision-porous hydrogel scaffold: ophthalmologic applications.
abstract: Appropriate mechanical properties and highly interconnected porosity are important properties for tissue engineering scaffolds. However, most existing hydrogel scaffolds suffer from poor mechanical properties limiting their application. Furthermore, it is relatively infrequent that precision control is achieved over pore size and structure of the scaffold because there are relatively few current technologies that allow such control and there is not a general appreciation that such control is important. To address these shortcomings, by combining double network polymerization and sphere-templating fabrication techniques, we developed a tough, intelligent scaffold based on poly(acrylic acid) and poly(N-isopropyl acrylamide) with a controllable, uniform, and interconnected porous structure. A mechanical assessment showed the toughness of the hydrogel and scaffold to be up to ∼1.4 × 10(7) Jm(-3) and ∼1.5 × 10(6) Jm(-3) respectively, as compared with 10(4)-10(5) Jm(-3) for most synthetic hydrogels. The thermosensitivity and pH-sensitivity were explored in a swelling study. In vitro testing demonstrated the scaffold matrices supported NIH-3T3 cell adhesion, proliferation and infiltration. An in vivo rabbit study showed the scaffolds promote strong cellular integration by allowing cells to migrate into the porous structure from the surrounding tissues. These data suggest that the poly(acrylic acid)/poly(N-isopropyl acrylamide)-based scaffold could be an attractive candidate for tissue engineering.
authors.affiliation: Eye Center, Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou 310009, China; Dept. of Ophthalmology, School of Medicine, University of Washington, Seattle, WA 98195, USA; Dept. of Bioengineering, University of Washington, Seattle, WA 98195, USA.
authors.forename: Wenqi
authors.initials: W
authors.lastname: Teng
authors.affiliation: Dept. of Bioengineering, University of Washington, Seattle, WA 98195, USA.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Long
authors.affiliation: Eye Center, Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou 310009, China.
authors.forename: Qianru
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Eye Center, Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou 310009, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Yao
authors.affiliation: Dept. of Ophthalmology, School of Medicine, University of Washington, Seattle, WA 98195, USA; Dept. of Bioengineering, University of Washington, Seattle, WA 98195, USA.
authors.forename: Tueng T
authors.initials: TT
authors.lastname: Shen
authors.affiliation: Dept. of Bioengineering, University of Washington, Seattle, WA 98195, USA. Electronic address: ratner@uweb.engr.washington.edu.
authors.forename: Buddy D
authors.initials: BD
authors.lastname: Ratner
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D002448:Cell Adhesion / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D005260:Female; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D020100:Hydrogels / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D051379:Mice; D008855:Microscopy, Electron, Scanning; D008954:Models, Biological; D041681:NIH 3T3 Cells; D009885:Ophthalmology / Q000379:methods*; D016062:Porosity; D011817:Rabbits; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D000180:Acrylic Resins; D001672:Biocompatible Materials; D020100:Hydrogels; C052970:poly-N-isopropylacrylamide; C006903:carbopol 940
keywords: 3D porous scaffold; Cellular integration; Mechanical properties; Poly(N-isopropyl acrylamide); Poly(acrylic acid); Tough hydrogels