Massive Fabrication of Polymer Microdiscs by Phase Separation and Freestanding Process.
We present a facile method to fabricate polymer thin films with tens of nanometers thickness and several micrometers size (also called "microdiscs" herein) by applying phase separation of polymer blend. A water-soluble supporting layer is employed to obtain a freestanding microdisc suspension. Owing to their miniaturized size, microdiscs can be injected through a syringe needle. Herein, poly(d,l-lactic acid) microdiscs were fabricated with various thicknesses and sizes, in the range from ca. 10 to 60 nm and from ca. 1.0 to 10.0 μm, respectively. Magnetic nanoparticles were deposited on polymer microdiscs with a surface coating method. The magnetic manipulation of microdiscs in a liquid environment under an external magnetic field was achieved with controllable velocity by adjusting the microdisc dimensions and the loading amount of magnetic components. Such biocompatible polymer microdiscs are expected to serve as injectable vehicles for targeted drug delivery.
Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University , 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan.|Department of Mechanical and Automation Engineering, Faculty of Engineering, The Chinese University of Hong Kong , Shatin, N.T., Hong Kong SAR China.|Micro/Nano Technology Center, Tokai University , 4-1-1 Kitakaname, Hiratsuka, Kanagawa 259-1292, Japan.
Hong
H
Zhang
Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University , 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan.
Mao
M
Fujii
Micro/Nano Technology Center, Tokai University , 4-1-1 Kitakaname, Hiratsuka, Kanagawa 259-1292, Japan.
Yosuke
Y
Okamura
Department of Mechanical and Automation Engineering, Faculty of Engineering, The Chinese University of Hong Kong , Shatin, N.T., Hong Kong SAR China.
Li
L
Zhang
Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University , 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan.
Shinji
S
Takeoka
freestanding; magnetic manipulation; microdisc; phase separation; polymer blend