title: Functional magnetic porous silica for T1-T2dual-modal magnetic resonance imaging and pH-responsive drug delivery of basic drugs.
abstract: A smart magnetic-targeting drug carrier γ-Fe2O3@p-silica comprising a γ-Fe2O3core and porous shell has been prepared and characterized. The particles have a uniform size of about 60 nm, and a porous shell of thickness 3 nm. Abundant hydroxyl groups and a large surface area enabled the γ-Fe2O3@p-silica to be readily loaded with a large payload of the basic model drug rhodamine B (RB) (up to 73 mg g-1). Cytotoxicity assays of the γ-Fe2O3@p-silica particles indicated that the particles were biocompatible and suitable for carrying drugs. It was found that the RB was released rapidly at pH 5.5 but at pH 7.4 the rate and extent of release was greatly attenuated. The particles therefore demonstrate an excellent pH-triggered drug release. In addition, the γ-Fe2O3@p-silica particles could be tracked by magnetic resonance imaging (MRI). A clear dose-dependent contrast enhancement in both T1-weighted and T2-weighted MR images indicated the potential of the γ-Fe2O3@p-silica particles to act as dual-mode T1and T2MRI contrast agents.
authors: Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Hubei University 430062, People's Republic of China. Key Laboratory of Green Preparation and Application for Materials, Ministry of Education, Hubei University 430062, People's Republic of China. Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, QLD, Australia.
authors: Ling
authors: L
authors: Li
authors: Run
authors: R
authors: Zhang
authors: Yi
authors: Y
authors: Guo
authors: Cheng
authors: C
authors: Zhang
authors: Wei
authors: W
authors: Zhao
authors: Zhiping
authors: Z
authors: Xu
authors: Andrew K
authors: AK
authors: Whittaker
mesh_terms: D016503:Drug Delivery Systems; D005290:Ferric Compounds; D008279:Magnetic Resonance Imaging; D008280:Magnetics; D012822:Silicon Dioxide
chemical_list: D005290:Ferric Compounds; D012822:Silicon Dioxide