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Published on: October 29, 2013
Dramatically Promoted Swelling of a Hydrogel by Pillar[6]arene-Ferrocene Complexation with Multistimuli
Mengfei Ni1, Ning Zhang1, Wei Xia1
1Key Laboratory of Mesoscopic Chemistry of MOE, Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University , Nanjing, 210023, China.
Abstract:
The swelling-shrinking transition of hydrogels is crucial for their wide applications such as actuators and drug delivery. We hereby fabricated a smart hydrogel with ferrocene groups on pendant of polymer networks. While it was immersed in the water-soluble pillar[6]arene (WP6) aqueous solution, the hydrogel was dramatically swollen, which was an approximately 11-fold promotion in weight compared with that in pure water, due to the formation of the inclusion complexes between WP6 and ferrocene groups in the hydrogel. In particular, the well-swollen hydrogel exhibited good responsiveness to multistimuli including temperature, pH, redox, and competitive guests by tuning the dissociation/formation of WP6-ferrocene inclusion complexes or the strength of their charges. Meanwhile, potential application of such a smart hydrogel in pH-responsive drug release was demonstrated as well.
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