title: Facile one-pot preparation, surface functionalization, and toxicity assay of APTS-coated iron oxide nanoparticles.
abstract: We report a facile approach to synthesizing 3-aminopropyltrimethoxysilane (APTS)-coated magnetic iron oxide (Fe(3)O(4)@APTS) nanoparticles (NPs) with tunable surface functional groups for potential biomedical applications. The Fe(3)O(4) NPs with a mean diameter of 6.5 nm were synthesized by a hydrothermal route in the presence of APTS. The formed amine-surfaced Fe(3)O(4)@APTS NPs were further chemically modified with acetic anhydride and succinic anhydride to generate neutral (Fe(3)O(4)@APTS⋅Ac) and negatively charged (Fe(3)O(4)@APTS⋅SAH) NPs. These differently functionalized NPs were extensively characterized by x-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, thermogravimetry analysis, zeta potential measurements, and T(2) relaxometry. The cytotoxicity of the particles was evaluated by in vitro 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide colorimetric viability assay of cells along with microscopic observation of cell morphology. The hemocompatibility of the particles was assessed  by in vitro hemolysis assay. We show that the hydrothermal approach enables an efficient modification of APTS onto the Fe(3)O(4) NP surfaces and the formed NPs with different surface charge polarities are water-dispersible and colloidally stable. The acetylated Fe(3)O(4)@APTS⋅Ac NPs displayed good biocompatibility and hemocompatibility in the concentration range of 0-100 µg ml(-1), while the pristine Fe(3)O(4)@APTS and Fe(3)O(4)@APTS⋅SAH particles started to display slight cytotoxicity at a concentration of 10 µg ml(-1). The findings from this study suggest that the Fe(3)O(4)@APTS NPs synthesized by the one-pot hydrothermal route can be surface modified for various potential biomedical applications.
authors.affiliation: College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, People's Republic of China.
authors.forename: Mingwu
authors.initials: M
authors.lastname: Shen
authors.forename: Hongdong
authors.initials: H
authors.lastname: Cai
authors.forename: Xifu
authors.initials: X
authors.lastname: Wang
authors.forename: Xueyan
authors.initials: X
authors.lastname: Cao
authors.forename: Kangan
authors.initials: K
authors.lastname: Li
authors.forename: Su He
authors.initials: SH
authors.lastname: Wang
authors.forename: Rui
authors.initials: R
authors.lastname: Guo
authors.forename: Linfeng
authors.initials: L
authors.lastname: Zheng
authors.forename: Guixiang
authors.initials: G
authors.lastname: Zhang
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Shi
mesh_terms: D000089:Acetic Anhydrides; D002470:Cell Survival / Q000187:drug effects; D004912:Erythrocytes; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D007624:KB Cells; D009682:Magnetic Resonance Spectroscopy; D058185:Magnetite Nanoparticles / Q000737:chemistry* / Q000633:toxicity*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D011437:Propylamines / Q000737:chemistry* / Q000633:toxicity*; D012821:Silanes / Q000737:chemistry* / Q000633:toxicity*; D013387:Succinic Anhydrides; D013499:Surface Properties
chemical_list: D000089:Acetic Anhydrides; D058185:Magnetite Nanoparticles; D011437:Propylamines; D012821:Silanes; D013387:Succinic Anhydrides; C088294:3-aminopropyltrimethoxysilane; C031800:acetic anhydride; C031801:succinic anhydride