title: Size-controlled synthesis, surface functionalization, and biological applications of thiol-organosilica particles.
abstract: Thiol-organosilica particles of a narrow size distribution, made from 3-mercaptopropyltrimethoxysilane (MPMS), were prepared by means of a one-pot synthesis. We examined three synthetic conditions at high temperature (100 degrees C), including the Stöber synthesis and two entirely aqueous syntheses. Under all conditions, the sizes of MPMS particles were well controlled, and the average of the coefficient of variation for the size distribution was less than 20%. The incubation times required for formation of MPMS particles were shorter at high temperature than at low temperature. MPMS particles internally functionalized with fluorescent dye were also prepared by means of the same one-pot synthesis. On flow cytometry analysis these MPMS particles showed distinct peaks of scattering due to well-controlled sizes of particles as well as due to fluorescence signals. Real-time observation of interaction between fluorescent MPMPS particles and cultured cells could be observed under fluorescent microscopy with bright light. The surface of the as-prepared MPMS particles contained exposed mercaptopropyl residues, and the ability to adsorb proteins was at least 6 times higher than that of gold nanopaticles. In addition, fluorescein-labeled proteins adsorbed to the surface of the particles were quantitatively detected at the pg/ml level by flow cytometry. MPMS particles surface functionalized with anti-CD20 antibody using adsorption could bind with lymphoma cells expressing CD20 specifically. In this paper, we demonstrated the possibility of size-controlled thiol-organosilica particles for wild range of biological applications.
authors.affiliation: Department of Anatomy and Cell Biology, University of Tokushima Graduate School of Medical Sciences, Tokushima 770-8503, Japan. michy@basic.med.tokushima-u.ac.jp
authors.forename: Michihiro
authors.initials: M
authors.lastname: Nakamura
authors.forename: Shuji
authors.initials: S
authors.lastname: Ozaki
authors.forename: Masahiro
authors.initials: M
authors.lastname: Abe
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Doi
authors.forename: Toshio
authors.initials: T
authors.lastname: Matsumoto
authors.forename: Kazunori
authors.initials: K
authors.lastname: Ishimura
mesh_terms: D000818:Animals; D018951:Antigens, CD20 / Q000378:metabolism; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D049452:Green Fluorescent Proteins / Q000737:chemistry; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D046529:Microscopy, Electron, Transmission; D008856:Microscopy, Fluorescence; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D017646:Organosilicon Compounds; D010316:Particle Size; D011485:Protein Binding; D012821:Silanes / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors
chemical_list: D018951:Antigens, CD20; D017646:Organosilicon Compounds; D012821:Silanes; D049452:Green Fluorescent Proteins; C102833:(3-mercaptopropyl)trimethoxysilane