Arnab
Halder and Qijin Chi* NanoChemistry Group, Department of Chemistry, Technical University of Denmark, Kongens Lyngby 2800, Denmark. *E-mail: cq@kemi.dtu.dk Graphene has emerged as a wonder material in
many fields ranging from physics and chemistry to biology in the past decade. [1]
Wet-chemical synthesis methods offer low-cost production and facile
functionalization of single-layered and solution suspended biocompatible
graphene. [2] We here used a biologically active molecule “Dopamine” (DA) for
the biofunctionalization. The unique properties of dopamine (DA) allow to be
used simultaneously as a reducing agent for GO reduction and as a capping
ligand to stabilize and decorate the resulting reduced GO (RGO) surface for
further functionalization. Moreover, as the dopamine moiety contains a redox
couple group, the hybrid material can be highly applicable to electrochemical
sensing. The catechol group of dopamine was selectively protected to prevent
from self-polymerization and undesirable side chain reactions. [3] After the
coupling reaction with graphene oxide, deprotection reaction was carried out to
recover free catechol groups in the RGO-DA nanocomposite. The HQ/Q- redox
couple in DA moiety can be highly applicable to electrochemical sensing. Here
we used this functionalized material for the electrochemical sensing of
melamine with ultra-high sensitivity. |