Hybrid nanoparticles with CO sub(2)-responsive shells and fluorescence-labelled magnetic cores

CO sub(2)-responsive polymer poly(N,N-diethylaminoethylmethacr ylate)-modified magnetic nanoparticles (Fe sub(3)O sub(4) sub(y)e/SiO sub(2)-PDEAEMA) were synthesized by atom transfer radical polymerization from the surfaces of silica coated, dye-labelled iron oxide nanoparticles (Fe sub(3)O sub(4) sub(y)e/SiO sub(2)). TEM, FT-IR, and TGA confirmed and quantified the grafted polymer brushes. The prepared magnetic nanoparticles (MNPs) were fluorescence labelled, as shown by the fluorescence spectra and fluorescence microscopy images. This indicated that the nanoparticles could be utilized as imaging probes to monitor the movement of biological cells or other systems. The PDEAEMA polymer brushes on the surface of MNPs endowed them with a protein adsorption ability. The polymer was also CO sub(2)-responsive, so it was a CO sub(2)-triggered reversible protein adsorption/release material, which was demonstrated by the bovine serum albumin (BSA) adsorption experiments. The results indicated that the reversible adsorption/release of protein by bubbling CO sub(2) and N sub(2) alternately was easy to achieve.