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

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.