When heated, the long chains of some polymers become more mobile. This increase in mobility expands the void space between the chains. We can use this property to make a “molecular switch” or a “micro/nano actuator” out of these polymers. Now, if we infiltrate these polymers with some macromolecules of interest and magnetic nanoparticles, when exciting them with high-frequency magnetic fields, the generated heat escalates the diffusion rate. The generated heat escalates the diffusion rate, thus enabling us to control the release of the macromolecules on demand.
For the purpose of illustration, PL and GA are shown in distinct colors with 50:50 length ratio. In reality, it is one long chain with the PL and GA distributed homogeneously along the length (as discussed in the paper).
More information: https://pubs.acs.org/doi/abs/10.1021/acs.nanolett.0c00648