Unusual Fe(CN)₆^3–/4– Capture Induced by Synergic Effect of Electropolymeric Cationic Surfactant and Graphene: Characterization and Biosensing Application

Herein, a special microheterogeneous system for Fe­(CN)₆^3–/4– capture was constructed based on graphene (GN) and the electropolymeric cationic surfactant, an amphiphilic pyrrole derivative, (11-pyrrolyl-1-yl-undecyl) triethylammonium tetrafluoroborate (A₂). The morphology of the system was characterized by scanning electron microscope. The redox properties of the entrapped Fe­(CN)₆^3–/4– were investigated by cyclic voltammetry and UV–visible spectrometry. The entrapped Fe­(CN)₆^3–/4– exhibited highly electroactive with stable and symmetrical cyclic voltammetric signal. A dramatic negative shift in the half wave potential can be obtained due to the unusual Fe­(CN)₆^3–/4– partitioning in in this microheterogeneous system based on poly­(A₂+GN). Finally, the entrapped Fe­(CN)₆^3–/4– was applied in the construction of the enhanced biosensors to hydrogen peroxide and sulfide.