Fabrication of novel superoxide anion biosensor based on 3D interface of mussel-inspired Fe3O4-Mn3(PO3)2@Ni foam

Preparation of high performance electrochemical biosensing interface for the sensitive and rapid detection of human metabolites is of great interest for health care and biomedical science. In this paper, based on the adhesion technique of marine mussels, we designed and prepared a novel biosensor with a micro/nano-biointerface of Fe 3 O 4 -Mn 3 (PO 3 ) 2 @Ni foam, which offered a three dimensional (3D) living environment for real cell. The constructed biosensor with a 3D micro/nano-biointerface of Fe 3 O 4 -Mn 3 (PO 3 ) 2 @Ni foam was characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and elemental mapping. Furthermore, the electrochemical experiments by electrochemical method for detection of superoxide anion (O 2 •− ) in situ released by cells were carried out by this biosensor we proposed. Results indicated that the 3D interface of mussel-inspired Fe 3 O 4 -Mn 3 (PO 3 ) 2 @Ni foam offered an amicable platform for promoting cell adhesion, which was beneficial for enhancing biosensing activity. This proposed sensing platform provided high electroactivity and excellent electron transport with a lower detection limit (0.0170   μM), wider linear range 0.04–2.44   μM) and short diffusion distance to reaction sites. The case achieved the accurate detection of O 2 •− (in situ released by cells) based on the combination of mussel-inspired biomimetic adhesion technique, 3D micro/nano-biointerface construction and electrochemical biosensing technique.