title: Fine-tuning in mineral cross-linking of biopolymer nanoparticle for incorporation and release of cargo.
abstract: We developed a mineral cross-linking strategy to prepare a biopolymer-based nanoparticle using calcium phosphate (CaP) as a cross-linker. Nanoparticles were first formed by mixing deoxyribonucleic acid (DNA) with cationic surfactants, and were cross-linked by CaP precipitation. After removal of the surfactants, we carried out the alternative dialysis of nanoparticles against CaCl2 aqueous solution and phosphate buffered solution for further mineral cross-linking. XRD and FT-IR studies revealed that the resultant nanoparticles were produced by mineral cross-linkages of hydroxyapatite (HAp) and the crystal amount and properties such as morphology and crystallinity could be well-controlled by the reaction conditions. Chemical dyes could be incorporated into nanoparticles via their affinities with crystal faces of HAp and DNA. Their release was tunable by crystal amount and properties of mineral cross-linkages. Also, the release could be triggered by mineral dissolution in response to pH. Such a mineral cross-linking will open up a potential way to provide a nanoparticle with versatile functions such as cleavable cross-linking, binding affinity for cargos, and pH-responsive release.
authors.affiliation: The Center for Chemical Biology, School of Fundamental Science and Technology, Graduate School of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
authors.forename: Yuuka
authors.initials: Y
authors.lastname: Fukui
authors.affiliation: The Center for Chemical Biology, School of Fundamental Science and Technology, Graduate School of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
authors.forename: Narumi
authors.initials: N
authors.lastname: Kabayama
authors.affiliation: The Center for Chemical Biology, School of Fundamental Science and Technology, Graduate School of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan. Electronic address: fujimoto@applc.keio.ac.jp.
authors.forename: Keiji
authors.initials: K
authors.lastname: Fujimoto
mesh_terms: D001704:Biopolymers / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000737:chemistry*; D004247:DNA / Q000737:chemistry; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D001704:Biopolymers; D002130:Calcium Phosphates; D003432:Cross-Linking Reagents; D004247:DNA; C020243:calcium phosphate
keywords: Alternative dialysis; Calcium phosphate; Cross-linking; DNA; Mineralization; Nanoparticle; Release control