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Alternating Magnetic Field-Responsive Hybrid Gelatin Microgels for Controlled Drug Release
Published on: February 13, 2016
Inducing and erasing of defect state in polymerized microgel colloidal crystals via external stimuli
Zhuo Tang1, Siyu Jia1, Lijuan Yao1
1Key Laboratory of Functional Polymer Materials and State Key Laboratory of Medicinal Chemical Biology, The Co-Innovation Center of Chemistry and Chemical Engineering of Tianjin, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China.
Abstract:
It remains a big challenge to introduce artificial extrinsic defects into colloidal crystals, which is critical for them to function as photonic crystals. The introduction of smart defects capable of responding to external stimuli is even harder. Here poly(N-isopropylacrylamide) (PNIPAM) microgel colloidal crystals doped with poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPAM-AAc)) microgel were obtained by self-assembly of the two microgels with the same size. The crystalline structure was then stabilized in situ by photo-initiated polymerization of the vinyl groups on surface of the PNIPAM microgel. Defect state can be facilely induced and then erased reversibly by changing pH or temperature, taking advantage of the different response of the two microgels to external stimuli. The defect state can be induced and erased repeatedly. In addition, the response of the doped crystals is fast because of their inherent porous structure.
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