We demonstrate the synthesis and characteristics of multifunctional poly(styrene-co-fluorescein O-methacrylate)/poly(N-isopropylacrylamide)-Fe 3O4 [P(St/FMA)/PNIPAAm-Fe3O4] core/shell composite particles, in which the core consists of fluorescent materials and the shell consists of magnetic and thermo-responsive components. First, core/shell particles consisting of a fluorescent P(St/FMA) core and thermo-responsive PNIPAAm-rich shell were prepared by two-stage shot-growth emulsion polymerization. Next, Fe3O4 nanoparticles were immobilized via electrostatic interactions and then covalently linked to the shell via surface coordinated Aphen by a coupling reaction in order to obtain magnetic properties. The morphology of P(St/FMA)/PNIPAAm-Fe3O 4 composite particles, confirmed by transmission electron microscopy (TEM), reveals that Fe3O4 nanoparticles are located in the PNIPAAm shell. The thermo-sensitivity of composite particles to hydrodynamic diameter was confirmed by using dynamic light scattering (DLS). Photoluminescence (PL) spectra indicate that the fluorescence emission intensity of core/shell particles is highly sensitive to the pH of an aqueous medium. The core/shell composite particles exhibited a combination of fluorescent, magnetic, pH and thermo-responsive behavior.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation (NRF) grant funded by the Korea government ( MEST ) through the Active Polymer Center for Pattern Integration (No. R11-2007-050-00000-0 and 2007-0052622 ) and a grant from the Industrial Technology Development program ( K0006005 ) of the Ministry of Knowledge Economy (MKE) of Korea. This research was supported by Future-based Technology Development Program (Nano Fields) through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology ( 2010-0019175 ). This work was also supported by the Seoul Research and Business Development Program (10816) and by the Pioneer Research Center Program though the National Research Foundation of Korea, funded by the Ministry of Education, Science and Technology (No. 2010-0019308 ). The authors acknowledge the financial support of the Ministry of Education through the second stage Brain Korea 21 Program at Yonsei University.
All Science Journal Classification (ASJC) codes
- Organic Chemistry
- Polymers and Plastics
- Materials Chemistry