The research interest of Takao Aoyagi is to develop the novel biomedical materials aiming at tissue engineering, cell function control, targeted drug delivery and so on. To achieve the purpose, he has intended to design monomer and polymer structure as well as the network, interface and self-assembly using the developed polymers. In Sagami Chemical Research Center, he investigated very unique polymeric transdermal penetration enhancers. The polymeric compounds did not penetrate through the skin by themselves and only promoted the drug penetration. There, he also developed temperature-responsive polymeric materials comprising poly (e-caprolactone)-based polyesters. The materials nicely controlled the drug permeation near body temperature.

 After he moved to Tokyo Women's medical University, he challenged the novel biomaterials design. One of the achievements is the design and synthesis of temperature-responsive polymeric micelles. Another is the development of N-isopropylacrylamide-based functional monomers and polymers. The resulting copolymers contain comonomer random sequences based on very similar copolymerization reactivity, as well as show both the good chemical reactivity and nice stimuli-response. This work attracts much attention because the polymeric materials can be applied to many kinds of biomedical use. Until then, such types of polymeric materials have not been available.

In Kagoshima University, he carried out both fundamental study of temperature-responsive property of N-isopropylacrylamide-based polymers and their biomedical application such as nanoparticle and surface modification. One of the topics is the coacervate formation of the polymers. Through the study, he made the temperature-responsive mechanism including phase transition and phase separation clear.

Another one is combination of the polymers with magnetite particles. He succeeded to immobilization of the polymer onto the magnetite nanoparticle surface. The combination of inductive heating by alternating magnetic field (AMF) and such stimuli-responsive polymers gives some unique biomedical application. The surface-modified magnetic nanoparticles showed the sensitive response to AMF. The similar concept was applied to development of AMF-responsive chromatography. Taking the scale-up of biomolecule separation into consideration, this separation system would have some advantages because of no use of water-miscible organic solvent that is required for a conventional reverse-phase chromatography.

In NIMS, he continues to study the design of novel biomaterial and biomedical evaluation. Recent topics are temperature-responsive nano-fiber, double responsive block copolymer, elastic biodegradable polymeric material and they are promising materials for new nano-bio fields.