Controlled stimulation-burst targeted release by smart decentered core–shell microcapsules in gravity and magnetic field

By combining gravity and magnetic force, we have developed a versatile and facile microfluidic method for forming magnetic decentered core–shell microcapsules in which the directions of the oil core and the magnetic nanoparticles are either opposed or the same. When the temperature rises above the LCST of the PNIPAm, the shell shrinks rapidly and the core targets burst release towards the converse or the same direction as the magnet. By adjusting the direction of the magnet, the release direction of the active substance could be correspondingly accurately controlled.