title: Ultrathin hybrid films of polyoxohydroxy clusters and proteins: layer-by-layer assembly and their optical and mechanical properties.
abstract: The hierarchical assembly of inorganic and organic building blocks is an efficient strategy to produce high-performance materials which has been demonstrated in various biomaterials. Here, we report a layer-by-layer (LBL) assembly method to fabricate ultrathin hybrid films from nanometer-scale ionic clusters and proteins. Two types of cationic clusters (hydrolyzed aluminum clusters and zirconium-glycine clusters) were assembled with negatively charged bovine serum albumin (BSA) protein to form high-quality hybrid films, due to their strong electrostatic interactions and hydrogen bonding. The obtained hybrid films were characterized by scanning electron microscope (SEM), UV-vis, Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray fluorescence (XRF), and X-ray diffraction (XRD). The results demonstrated that the cluster-protein hybrid films exhibited structural homogeneity, relative transparency, and bright blue fluorescence. More importantly, these hybrid films displayed up to a 70% increase in hardness and up to a 100% increase in reduced Young's modulus compared to the pure BSA film. These hybrid cluster-protein films could be potentially used as biomedical coatings in the future because of their good transparency and excellent mechanical properties.
authors.affiliation: Division of Nanomaterials & Chemistry, Hefei National Laboratory for Physical Sciences at Microscale, Collaborative Innovation Center of Suzhou Nano Science and Technology, Department of Chemistry, University of Science and Technology of China , Hefei 230026, PR China.
authors.forename: You-Xian
authors.initials: YX
authors.lastname: Yan
authors.forename: Hong-Bin
authors.initials: HB
authors.lastname: Yao
authors.forename: Scott E
authors.initials: SE
authors.lastname: Smart
authors.forename: Li-Bo
authors.initials: LB
authors.lastname: Mao
authors.forename: Wei
authors.initials: W
authors.lastname: Hu
authors.forename: Shaotang
authors.initials: S
authors.lastname: Yuan
authors.forename: Laurence
authors.initials: L
authors.lastname: Du-Thumm
authors.forename: James G
authors.initials: JG
authors.lastname: Masters
authors.forename: Shu-Hong
authors.initials: SH
authors.lastname: Yu
authors.forename: Long
authors.initials: L
authors.lastname: Pan
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D002417:Cattle; D008855:Microscopy, Electron, Scanning; D011108:Polymers / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D001672:Biocompatible Materials; D011108:Polymers; D012710:Serum Albumin, Bovine