Magnetic and Temperature-Sensitive Composite Polymer Particles and Adsorption Behavior of Emulsifiers and Trypsin

A combination of magnetic and temperature-responsive properties in the same polymer composites is expected to increase their potential applications in the biomedical field. Accordingly, micron-sized magnetite/polystyrene/poly(2-dimethylaminoethyl methacrylate-ethyleneglycol dimethacrylate), which are abbreviated as Fe 3 O 4 /PS/P (DM-EGDM) composite polymer particles, were prepared by the seeded copolymerization of DM and EGDM in the presence of magnetite/polystyrene (Fe 3 O 4 /PS) particles. Fe 3 O 4 /PS/P(DM-EGDM) composite particles with magnetic properties showed a temperature-sensitive phase transition at approximately 31 oC. The adsorption behavior of the low molecular weight emulsifiers and trypsin (TR) as biomolecules were examined on Fe 3 O 4 /PS/P(DM-EGDM) composite polymer particles at different temperatures. The native conformation of TR was followed by measuring the specific activity under various adsorption conditions. The activity of the adsorbed TR on composite polymer particles was higher than those of the free TR and TR adsorbed on Fe 3 O 4 /PS particles.