Investigation On Janus Nanospheres With Shape Memory Function

Janus particles have attracted increasing attention from the communities of materials science,chemistry,physics and biology.However,the nanoscale Janus particles that can switch shapes in response to an environmental stimulus is a significant challenge.In this article,we have demonstrated a simple procedure to fabricate the amphipathic Janus nanoparticles composed of hydrophilic body and hydrophobic lobe via using sudden negative pressure technique.Moreover,in response to temperature,the nanoparticles can recover to their initial nanosphere state by a switchable process,showing promising shape memory effect.Here,we can monitor the switchable nanostructures with hydrophilic and hydrophobic changes in the shape memory process of the JNPs by transmission electron microscope TEM,DLS and WCA.Furthermore,we successfully compare the differences of shape deformation ratio and shape recovery ratio using the three test methods by the statistical analysis of Student’s t test for independent samples.In addition,we also develop a hybrid magnetic Janus nanoparticle changed from the amphipathic Janus nanoparticles by the selective attachment of magnetic nanoparticles with hydrophobic molecules,which shows new Janus nanostructure and shape memory property.Moreover,with the addition of magnetic nanoparticles,the magnetic area of the magnetic Janus nanoparticles gradually increases.Subsequently,we have also prepared a novel type of magnetic shelled core/shell microsphere.The microsphere possesses an optimized inner cavity and a strong magnetic property.Furthermore,the microsphere has different rupture modes at different pH conditions,including “swelling-broken”,“dissociating-broken”,and “burstingbroken” modes.Finally,we investigate the in vitro release behaviors of the hollow core/shell structured carrying Nile Red at different pH conditions.We find with the acidity increases,the ratio of the Nile Red in vitro release increases.