文献类型：期刊文献

英文题名：A magnetic, reversible pH-responsive nanogated ensemble based on Fe₃O₄ nanoparticles-capped mesoporous silica

作者：Gan, Qi[1,3];Lu, Xunyu[3];Yuan, Yuan[1,3];Qian, Jiangchao[1];Zhou, Huanjun[2];Lu, Xun[2];Shi, Jianlin[2];Liu, Changsheng[1,2,3]

机构：[1]E China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]E China Univ Sci & Technol, Minist Educ, Key Lab Ultrafine Mat, Shanghai 200237, Peoples R China;[3]E China Univ Sci & Technol, Minist Educ, Engn Res Ctr Biomed Mat, Shanghai 200237, Peoples R China

年份：2011

卷号：32

期号：7

起止页码：1932

外文期刊名：BIOMATERIALS

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000287069400019)】；

基金：The authors wish to express their gratitude to the financial supports from Major Program of National Natural Science Foundation of China (No. 50732002), Shanghai Nanotechnology Special Foundation (No. 0952nm05400), Shanghai Science and Technology Commission (No. 09410709100 and 10540709800) and Program for Changjiang Scholars and Innovative Research Team in University (IRT0825). We also greatly thank Dr Shengnian Wang of Louisiana Tech University for his good advices and English modification.

语种：英文

外文关键词：pH-responsive; Mesoporous silica; Magnetic; Gate-like; Biocompatibility

摘要：Stimuli-sensitive mesoporous silica nanoparticles (MSNs)-based hybrid "gate-like" ensembles capable of performing specific programmed release mode represent a new generation delivery system in recent years. In this paper, a magnetic and reversible pH-responsive. MSNs-based nanogated ensemble was fabricated by anchoring superparamagnetic Fe3O4 nanoparticles on the pore outlet of MSNs via a reversible boronate esters linker. To achieve this, MSNs and Fe3O4 nanoparticles were first synthesized and functionalized by polyalcohol derivative and boronic acid, respectively. The successful incorporation of Fe3O4 nanoparticles onto the MSNs was confirmed by the results of XRD, TEM, XPS and N-2 adsorption-desorption method. The pH-driven "gate-like" effect was studied by in vitro release of an entrapped model dexamethasone from the pore voids into the bulk solution at different pH values. The results indicated that at pH 5-8, the pores of the MSNs were effectively capped with Fe3O4 nanoparticles and the drug release was strongly inhibited. While at pH 2-4, the hydrolysis of the boroester bond took place and thus resulted in a rapid release of the entrapped drug. And by alternately changing the pH from 3 to 7, these Fe3O4 cap gate could be switched "on" and "off" and thereby released the entrapped drug in a pulsinate manner (in small portions). Additionally, this nanogated release system exhibited good magnetic property, high cell biocompatibility and cellular uptake for MC3T3-E1 cells. The present data suggest that it is possible to obtain simple and very effective pH-driven pulsinate release using these Fe3O4-capped-MSNs, and this new platform represents a promising candidate in the formulation of in vivo targeted delivery of therapeutic agents to low pH tissues, such as tumors and inflammatory sites. (C) 2010 Elsevier Ltd. All rights reserved.