A novel biosensor based on a gold nanoflowers/hemoglobin/carbon nanotubes modified electrode

Abstract

Well-oriented 3D gold flower-like nanoparticles were successfully synthesized by a facile one-pot method, and the gold nanoflowers (AuNFs) were mixed with hemoglobin (Hb) to form a gold nanoflowers/hemoglobin composite. The composite was further combined with multiwalled carbon nanotubes on a glassy carbon electrode (GCE) to fabricate a novel biosensor. The sensor has high stability and bioactivity, and was studied by scanning electron microscopy (SEM) and cyclic voltammetry (CV). The hemoglobin/gold nanoflowers/multiwalled carbon nanotubes glassy carbon electrode (Hb/AuNFs/CNTs/GCE) either retained the Hb in similar native conformations or promoted direct electron transfer. Moreover, the sensor exhibited remarkable catalytic activity toward H₂O₂ and trichloroacetic acid (TCA). The linear relationship for the determination is in the range of 1.0–60 μM for H₂O₂ and 0.06–28 mM for TCA. The detection limits were 0.08 μM and 7.3 μM (S/N = 3), respectively.