초록 |
Dual-responsive DNA block copolymer was synthesized by coupling a thermo-responsive polymer, poly(N-isopropylacrylamide (PNIPAM) and an oligonucleotide. DNA-b-PNIPAM possesses thermo-responsive properties of PNIPAM as well as molecular recognition properties of DNA. DNA triblock copolymers of DNA-b-PNIPAM-b-PMA was also synthesized by introducing a hydrophobic block, poly(methyl acrylate) (PMA) to DNA/PNIPAM block copolymers, which form spherical micelles at room temperature. DNA-b-PNIPAM-b-PMA micelles undergo sphere-to-cylinder shape changes above LCST due to the conformational change of PNIPAM. The low temperature spherical morphology can also be accessed while keeping the temperature above LCST by introducing complimentary DNA strands with single stranded overhang regions. These results demonstrate the multi-dimensional shape changing capability of DNA-b-PNIPAM-b-PMA enabled by the dual-responsive property. |