Preparation And Performance Of Photopolymerization Polyvinyl Alcohol Nanocomposite Hydrogel

Poly(vinyl alcohol)(PVA)hydrogels has been widely studied for various biomedical applications,due to their tissue-like viscoelasticity and excellent biocompatibility.However,PVA hydrogels are often brittle and intrinsically cell nonadhesive,limiting their applications to in vivo translation.To improve their mechanical properties and cell affinity,addition of bioactive nanomaterials into PVA hydrogels to achieve nanocomposite hydrogels provides a good approach.In this study,firstly,methacrylated PVA(PVA-GMA)and carboxyl-modified methacrylated PVA(COOH-PVA-GMA)were synthesized,and then three nanocomposite hydrogels including methacrylate-functionalized silica nanoparticles/methacrylated PVA(MSi/PVA-GMA)system,hydroxyapatite/methacrylated PVA(HAP/PVA-GMA)system and hydroxyapatite/carboxyl-modified methacrylated PVA(HAP/COOH-PVA-GMA)system by a photopolymerization technique.A series of properties of the photocrosslinkable nanocomposite hydrogels including rheological property,swelling kinetics,morphology,crystallinity etc.are investigated by photo-rheology,scanning electron microscopy(SEM),differential scanning calorimetry(DSC)and X-ray diffraction(XRD),respectively.The in vitro cytotoxic evaluation and cell culture of the hydrogels in combination with mouse articular chondrocytes are also studied to demonstrate their potential as tissue engineering scaffolds.Main results are as follows.(1)The MSi/PVA-GMA nanocomposite hydrogel system.Compress stress of the hydrogels at the strain of 90% increased from 7.35 MPa to 16.7 MPa,and stress at break,tensile strain at break and elastic modulus of the hydrogels increased from 39.6 kPa,211.2%,34.0 kPa to 610.7 kPa,544.6%,492.0 kPa,respectively,due to introduction of MSi.Furthermore,indirect cytotoxicity assessment indicated that the hydrogels were nontoxic to the L929 cell.Cell culture results showed that the hydrogels were good in promoting the cell attachment and proliferation.(2)The HAP/PVA-GMA nanocomposite hydrogel system.Compress stress of the hydrogels at the strain of 90% increased from 0.99 MPa to 2.17 MPa,and stress at break,tensile strain at break and elastic modulus of the hydrogels increased from 40.7 kPa,199.6%,20.2 kPa to 376.4 kPa,795.5%,148.5 kPa,respectively,due to introduction of HAP.Furthermore,indirect cytotoxicity assessment indicated that the hydrogels were nontoxic to the L929 cell.Cell culture results showed that the hydrogels can support cell attachment and proliferation.(3)The HAP/COOH-PVA-GMA nanocomposite hydrogel system.Compress stress of the hydrogels at the strain of 90% increased from 6.7 MPa to 129 MPa,and tensile strain at break of the hydrogels increased from 215.6% to 865.4%,due to introduction of HAP.Furthermore,indirect cytotoxicity assessment indicated that the hydrogels were nontoxic to the L929 cell.Cell culture results showed that the hydrogels were good in promoting the cell attachment and proliferation,due to introduction of-COOH group of COOH-PVA-GMA and HAP.The above-mentioned photopolymerizable PVA-based nanocomposite hydrogels could gel fast and had excellent mechanical properties and biocompatibility,as well as outstanding cell adhesion,which made them as potential tissue engineering scaffolds.