Multifunctional Up‐Converting Nanocomposites with Smart Polymer Brushes Gated Mesopores for Cell Imaging and Thermo/pH Dual‐Responsive Drug Controlled Release. (27th March 2013)

• Record Type: Journal Article
• Authors: Zhang, Xiao; Yang, Piaoping; Dai, Yunlu; Ma, Ping'an; Li, Xuejiao; Cheng, Ziyong; Hou, Zhiyao; Kang, Xiaojiao; Li, Chunxia; Lin, Jun
• Is Part Of: Advanced functional materials. Volume 23:Number 33(2013)
• Page Start: 4067
• Page End: 4078
• Publication Date: 2013-03-27
• Subjects: Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.201300136
• Languages: English
• ISSNs: 1616-301X

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>Multifunctional nanocarriers based on the up‐conversion luminescent nanoparticles of NaYF<sub>4</sub>:Yb<sup>3+</sup>/Er<sup>3+</sup> core (UCNPs) and thermo/pH‐coupling sensitive polymer poly[(<italic>N</italic>‐isopropylacrylamide)‐<italic>co</italic>‐(methacrylic acid)] (P(NIPAm‐<italic>co</italic>‐MAA)) gated mesoporous silica shell are reported for cancer theranostics, including fluorescence imaging, and for controlled drug release for therapy. The as‐synthesized hybrid nanospheres UCNPs@mSiO<sub>2</sub>‐P(NIPAm‐<italic>co</italic>‐MAA) show bright green up‐conversion fluorescence under 980 nm laser excitation and the thermo/pH‐sensitive polymer is active as a "valve" to moderate the diffusion of the embedded drugs in‐and‐out of the pore channels of the silica container. The anticancer drug doxorubicin hydrochloride (DOX) can be absorbed into UCNPs@mSiO<sub>2</sub>‐P(NIPAm‐<italic>co</italic>‐MAA) nanospheres and the composite drug delivery system (DDS) shows a low level of leakage at low temperature/high pH values but significantly enhanced release at higher temperature/lower pH values, exhibiting an apparent thermo/pH controlled "on‐off" drug release pattern. The as‐prepared UCNPs@mSiO<sub>2</sub>‐P(NIPAm‐<italic>co</italic>‐MAA) hybrid nanospheres can be used as bioimaging agents and biomonitors to track the extent of drug release. The reported multifunctional nanocarriers represent a novel and versatile class of platform for simultaneous imaging and stimuli‐responsive controlled drug delivery.</p> </abstract>