Corresponding Author

Yuan-hua SHAO(yhshao@pku.edu.cn)


Room temperature ionic liquid (RTIL) is used as a soft-template to organize a meso-macroporous material constructed by self-assembled giant gold nanoparticles which are capped by L-cysteine. First, L-cysteine capped gold nanoparticles can self-assembly to form nanowires and sub-micrometer spherical giant particles due to the static interaction and/or the condensation reaction between the carboxyl and amino groups at the outer terminal of the ligand. Second, the spherical assembled particles can form a quasi-solid gel when grinding with a hydrophobic RTIL, 1-octyl-3-metyllimidazolium hexafluorophosphate. Finally, when the composite gel is coated on a glassy carbon electrode and then polarized by using cyclic voltammetry in phosphate buffer solution (PBS, pH = 7.4), a meso-macroporous structure is formed due to the leakage of the surplus of RTIL in the gel. This meso-macroporous structured material has a good conductivity and affinity to biological macromolecules. The faradaic current of cytochrome c can be enhanced significantly due to both the high outer surface area and the inner “thin-layer” effect. The experimental results indicate that this novel meso-macroporous material has potential application for electrochemical devices including biosensors and biofuel cells.

Graphical Abstract


room temperature ionic liquid, self-assemble, gold nanoparticles, cytochrome c, biosensors

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