Hollow PUA/PSS/Au microcapsules with interdependent near‐infrared/pH/temperature multiresponsiveness

Abstract

In this work, smart hollow microcapsules made of thermal-/pH-dual sensitive aliphatic poly(urethane-amine) (PUA), sodium poly(styrenesulfonate) (PSS), and Au nanoparticles (AuNPs) for interdependent multi-responsive drug delivery have been constructed by layer-by-layer (LbL) technique. The electrostatic interactions among PUA, PSS, and AuNPs contribute to the successful self-assembly of hollow multilayer microcapsules. Thanks to the shrinkage of PUA above its lower critical solution temperature (LCST) and the interaction variation between PUA and PSS at different pH conditions, hollow microcapsules exhibit distinct pHand thermal-sensitive properties. Moreover, AuNPs aggregates can effectively convert light to heat upon irradiation with near-infrared (NIR) laser and endow the hollow microcapsules with distinct NIR-responsiveness. More importantly, the NIR-responsive study also demonstrates that the microcapsule morphology and the corresponding NIR-responsive drug release are strongly dependent on the pH value and temperature of the media. The results indicate that the prepared hollow PUA/PSS/Au microcapsules have the great potential to be used as a novel smart drug carrier for the remotely controllable drug delivery. V C 2015 Wiley Periodicals, Inc. J. Appl. Polym.Sci. 2016, 133, 43008.

Surface Permeability of Membrane and Catalytic Performance Based on Redox-Responsive of Hybrid Hollow Polymeric Microcapsules

“…Due to the combination of different applications with hollow microcompartment, a way to control the membrane permeable based on environment response is a key concern and should be designed first. Scientists paid more attention to making hollow microcompartments undergo a chemical or physical change in response to environmental stimuli such as pH, temperature, redox species, light, magnetic, and electric fields [ 5 , 6 , 7 , 8 , 9 ]. In general, these chemical or physical changes will lead to the self-assembly of porous membranes, resulting in the breakage or re-formation of channel pores at the edges of the membranes.…”

Exploiting thermally-reversible covalent bonds for the controlled release of microencapsulated isocyanate crosslinkers

“…change in pH or solvent), [10,11] light, [12,13] ultrasound [14,15] and exposure to elevated temperature. [16][17][18][19][20][21][22][23][24] Release of the core contents from microcapsules using heat can be achieved by heating above the boiling point or degradation temperature of the encapsulated core to increase the internal pressure sufficient to cause rupture of the microcapsule shell. [17,18,22] This approach has been further developed by adhering microcapsules containing blowing agents to magnetic particles -upon application of a magnetic field the particles oscillate creating localised hotspots sufficient to induce degradation of the encapsulated blowing agent, raising the internal pressure and bursting the microcapsules.…”