title: Facile solvothermal synthesis of mesostructured Fe3O4/chitosan nanoparticles as delivery vehicles for pH-responsive drug delivery and magnetic resonance imaging contrast agents.
abstract: We report a facile fabrication of a host-metal-guest coordination-bonding system in a mesostructured Fe3O4/chitosan nanoparticle that can act as a pH-responsive drug-delivery system. The mesostructured Fe3O4/chitosan was synthesized by a solvothermal approach with iron(III) chloride hexahydrate as a precursor, ethylene glycol as a reducing agent, ammonium acetate as a porogen, and chitosan as a surface-modification agent. Subsequently, doxorubicin (DOX), acting as a model drug (guest), was loaded onto the mesostructured Fe3O4/chitosan nanoparticles, with chitosan acting as a host molecule to form the NH2-Zn(II)-DOX coordination architecture. The release of DOX can be achieved through the cleavage of coordination bonds that are sensitive to variations in external pH under weakly acidic conditions. The pH-responsive nature of the nanoparticles was confirmed by in vitro releases and cell assay tests. Furthermore, the relaxation efficiency of the nanoparticles as high-performance magnetic resonance imaging contrast agents was also investigated. Experimental results confirm that the synthesized mesostructured Fe3O4/chitosan is a smart nanovehicle for drug delivery owing to both its pH-responsive nature and relaxation efficiency.
authors.affiliation: State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000 (P.R. China), Fax: (+86) 931-8912113. zhaogh@lzu.edu.cn.
authors.forename: Guanghui
authors.initials: G
authors.lastname: Zhao
authors.forename: Jianzhi
authors.initials: J
authors.lastname: Wang
authors.forename: Xiaomen
authors.initials: X
authors.lastname: Peng
authors.forename: Yanfeng
authors.initials: Y
authors.lastname: Li
authors.forename: Xuemei
authors.initials: X
authors.lastname: Yuan
authors.forename: Yingxia
authors.initials: Y
authors.lastname: Ma
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000737:chemistry / Q000633:toxicity; D002470:Cell Survival / Q000187:drug effects; D048271:Chitosan / Q000737:chemistry*; D003287:Contrast Media / Q000737:chemistry / Q000378:metabolism; D004317:Doxorubicin / Q000737:chemistry / Q000633:toxicity; D004337:Drug Carriers / Q000138:chemical synthesis / Q000737:chemistry*; D052203:Ferrosoferric Oxide / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008279:Magnetic Resonance Imaging; D053758:Nanoparticles / Q000737:chemistry*; D016062:Porosity; D015032:Zinc / Q000737:chemistry
chemical_list: D000903:Antibiotics, Antineoplastic; D003287:Contrast Media; D004337:Drug Carriers; D004317:Doxorubicin; D048271:Chitosan; D015032:Zinc; D052203:Ferrosoferric Oxide
keywords: drug delivery; imaging agents; magnetic properties; nanoparticles; pH responses