Development of Magnetic Microbeads Equipped with Temperature-Responsive Artificial Antibodies for Efficient...

In this study, micrometer-sized magnetic beads equipped with artificial antibodies whose reactivity could be controlled by temperature tuning were developed. An artificial antibody that can specifically bind to doxorubicin (Dox) was fabricated on an N-isopropylacrylamide copolymer matrix on the surface of the magnetic beads. The growth reaction of gold nanoparticles (NPs) was effectively used to promote the selective polymerization reaction on the beads. To develop magnetism and polymerization via the growth of gold NPs, plastic beads were coated with both magnetic iron oxide and gold NPs. The fluorescence microscopy evaluation of the fabricated artificial antibody revealed that the temperature-dependent affinity change in the copolymer reversibly changed its binding properties upon temperature control. This engineered antibody is effective against anthracyclines with complex molecular structures and exhibits excellent selectivity (>50-fold). This development makes the efficient separation and recovery of Dox contained in human plasma samples using an external magnetic force and temperature control feasible. The results of this study could guide the development of highly efficient artificial antibodies that could revolutionize cancer treatment.