Highly efficient DNA release was achieved by the polyamidoamine-modified superparamagnetic particles (PAMAM–SpMNPs) that were prepared with 10-nm magnetite cores. We optimized the surface amine numbers of the PAMAM–SpMNPs to control the interaction between a DNA molecule and the amine groups on the particle. With this optimization, the PAMAM–SpMNPs maintained a high DNA adsorption capacity and high dispersivity in solution. The DNA-release efficiency using PAMAM–SpMNPs was over 95%. Furthermore, the complete DNA release from PAMAM–SpMNPs was achieved by applying an alternating magnetic field for 10 min.
- Atsushi Arakaki
- Keiyu Shibata
- Tsuyoshi Tanaka