title: Phase behavior of poly(sulfobetaine methacrylate)-grafted silica nanoparticles and their stability in protein solutions.
abstract: Biocompatible and zwitterionic poly(sulfobetaine methacrylate) (PSBMA) was grafted onto the surface of initiator-modified silica nanoparticles via surface-initiated atom transfer radical polymerization. The resultant samples were characterized via nuclear magnetic resonance, Fourier transform infrared spectroscopy, transmission electron microscopy, and thermogravimetric analysis. Their molecular weights and molecular weight distributions were determined via gel permeation chromatography after the removal of silica by etching. Moreover, the phase behavior of these polyzwitterionic-grafted silica nanoparticles in aqueous solutions and stability in protein/PBS solutions were systematically investigated. Dynamic light scattering and UV-visible spectroscopy results indicate that the silica-g-PSBMA nanoparticles exhibit an upper critical solution temperature (UCST) in aqueous solutions, which can be controlled by varying the PSBMA molecular weight, ionic strength, silica-g-PSBMA nanoparticle concentration, and solvent polarity. The UCSTs shift toward high temperatures with increasing PSBMA molecular weight and silica-g-PSBMA nanoparticle concentration. However, increasing the ionic strength and solvent polarity leads to a lowering of the UCSTs. The silica-g-PSBMA nanoparticles are stable for at least 72 h in both negative and positive protein/PBS solutions at 37 °C. The current study is crucial for the translation of polyzwitterionic solution behavior to surfaces to exploit their diverse properties in the development of new, smart, and responsive coatings.
authors: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Changchun 130022, People's Republic of China.
authors: Zhixin
authors: Z
authors: Dong
authors: Jun
authors: J
authors: Mao
authors: Muquan
authors: M
authors: Yang
authors: Dapeng
authors: D
authors: Wang
authors: Shuqin
authors: S
authors: Bo
authors: Xiangling
authors: X
authors: Ji
mesh_terms: D001622:Betaine / Q000031:analogs & derivatives* / Q000737:chemistry; D001672:Biocompatible Materials / Q000032:analysis / Q000737:chemistry*; D002850:Chromatography, Gel; D005609:Free Radicals; D009682:Magnetic Resonance Spectroscopy; D008689:Methacrylates / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D008970:Molecular Weight; D009113:Muramidase / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D009994:Osmolar Concentration; D044367:Phase Transition; D058105:Polymerization; D012710:Serum Albumin, Bovine / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D012996:Solutions; D012997:Solvents / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D013818:Thermogravimetry; D014867:Water / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D005609:Free Radicals; D008689:Methacrylates; D012996:Solutions; D012997:Solvents; D014867:Water; D012710:Serum Albumin, Bovine; D001622:Betaine; D012822:Silicon Dioxide; C483727:sulfobetaine; D009113:Muramidase