Hemin–G-quadruplex-crosslinked poly-N-isopropylacrylamide hydrogel: a catalytic matrix for the deposition of conductive polyaniline. Issue 11 (27th August 2015)

• Record Type: Journal Article
• Authors: Lu, Chun-Hua; Guo, Weiwei; Qi, Xiu-Juan; Neubauer, Avner; Paltiel, Yossi; Willner, Itamar
• Is Part Of: Chemical science. Volume 6:Issue 11(2015:Nov.)
• Page Start: 6659
• Page End: 6664
• Publication Date: 2015-08-27
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c5sc02203g
• Languages: English
• ISSNs: 2041-6520

Abstract

Abstract : Conducting polyaniline is deposited into a G-quadruplex-crosslinked pNIPAM copolymer undergoing switchable stimuli-responsive solution/hydrogel/solid transitions. Abstract : A G-rich nucleic acid-tethered acrylamide/ N -isopropylacrylamide (NIPAM) copolymer is prepared. The nucleic acid-modified pNIPAM chains assemble, in the presence of K + ions, into a stimuli-responsive G-quadruplex-crosslinked pNIPAM hydrogel undergoing cyclic and reversible solution/hydrogel/solid transitions. Addition of kryptofix [2.2.2], CP, to the K + -stabilized G-quadruplex-crosslinked hydrogel eliminates the K + ions from the crosslinking units, resulting in the transition of the hydrogel into a pNIPAM solution. In turn, heating the pNIPAM hydrogel from 25 °C to 40 °C results in the transition of the hydrogel to the solid state, and cooling the solid to 25 °C restores the hydrogel state. Incorporation of hemin into the G-quadruplex-crosslinked hydrogel results in a catalytic hydrogel that catalyzes the oxidation of aniline by H2 O2 to form polyaniline. The polyaniline/pNIPAM hydrogel hybrid doped with 2 M HCl forms an emeraldine salt, which exhibits an electrical conductivity of 9 × 10 −4 [cm Ω] −1 .