A novel biomimetic nanoenzyme based on ferrocene derivative polymer NPs coated with polydopamine

In this paper, ferrocene derivative polymer nanoparticles (FcP NPs) with uniform size and good photostability was synthesized using 1,1'-ferrocene dicarboxylic acid as precursor and methanol as solvent. FcP NPs-PDA was further obtained by coating of polydopamine (PDA) on FcP NPs in tris-HCl (pH=8.5) buffer solution at room temperature in the presence of dopamine (DA). The structure and morphology of FcP NPs and FcP NPs-PDA were characterized by transmission electron microscope (TEM), ultraviolet-visible spectroscopy (UV-Vis), and infrared radiation (FT-IR). The as-prepared FcP NPs-PDA showed better peroxidase-like activity than FcP NPs, which could catalyze the chromogenic reaction of peroxidase substrate TMB, OPD and ABTS. Based on the high peroxidase-like property of FcP NPs-PDA, a sensitive and convenient means to detect H₂O₂ has been proposed with TMB as the substrate, which displays wide linear range of 10-600 μM and 600 μM-4 mM with low detection limit of 5 μΜ. Compared with other Fe-containing NPs, such as magnetic materials and noble metal@Fe bimetallic NPs, the preparation approach for FcP NPs-PDA is simple, time and energy saving and environment friendly. This mild and simple synthesis route of FcP NPs-PDA will provide new ideas for the preparation of non-noble metal-based peroxidase-like nanomaterials and widen the applications in the fields of catalytic and analytical chemistry.