title: Nanocomposite scaffold with enhanced stability by hydrogen bonds between collagen, polyvinyl pyrrolidone and titanium dioxide.
abstract: In this study, three-dimensional (3D) nanocomposite scaffolds, as potential substrates for skin tissue engineering, were fabricated by freeze drying the mixture of type I collagen extracted from porcine skin and polyvinyl pyrrolidone (PVP)-coated titanium dioxide (TiO2) nanoparticles. This procedure was performed without any cross-linker or toxic reagents to generate porosity in the scaffold. Both morphology and thermal stability of the nanocomposite scaffold were examined. The swelling behavior, mechanical properties and hydrolytic degradation of the composite scaffolds were carefully investigated. Our results revealed that collagen, PVP and TiO2 are bonded together by four main hydrogen bonds, which is an essential action for the formation of nanocomposite scaffold. Using Coasts-Redfern model, we were able to calculate the thermal degradation apparent activation energy and demonstrated that the thermal stability of nanocomposites is dependent on amount of PVP incorporated. Furthermore, SEM images showed that the collagen fibers are wrapped and stabilized on scaffolds by PVP molecules, which improve the ultimate tensile strength (UTS). The UTS of PVP-contained scaffold is four times higher than that of scaffold without PVP, whereas ultimate percentage of elongation (UPE) is decreased, and PVP can enhance the degradation resistance.
authors.affiliation: School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, PR China.
authors.forename: Na
authors.initials: N
authors.lastname: Li
authors.affiliation: School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, PR China.
authors.forename: Xialian
authors.initials: X
authors.lastname: Fan
authors.affiliation: School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, PR China. Electronic address: kytang@zzu.edu.cn.
authors.forename: Keyong
authors.initials: K
authors.lastname: Tang
authors.affiliation: School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, PR China.
authors.forename: Xuejing
authors.initials: X
authors.lastname: Zheng
authors.affiliation: School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.affiliation: Luoyang Petrochemical Engineering Corporation, SINOPEC, Luoyang 471003, PR China.
authors.forename: Baoshi
authors.initials: B
authors.lastname: Wang
mesh_terms: D000818:Animals; D003094:Collagen / Q000737:chemistry*; D006860:Hydrogen Bonding; D008855:Microscopy, Electron, Scanning; D015394:Molecular Structure; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D011205:Povidone / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D013552:Swine; D013696:Temperature; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: C009495:titanium dioxide; D003094:Collagen; D014025:Titanium; D011205:Povidone
keywords: Nanocomposite scaffold; Polyvinyl pyrrolidone; Stability; Titanium dioxide; Type I collagen