Amperometric biosensor based on nanoporous nickel/boron-doped diamond film for electroanalysis of l-alanine

This paper presents an electrochemical biosensor for the detection of l-alanine based on a nanoporous (NP) nickel (Ni)-modified boron-doped diamond (BDD) electrode. Self-supporting BDD films are prepared using an electron-assisted hot filament chemical vapor deposition method. Electrochemical studies show that increased surface concentration of redox moieties on the NP-Ni/BDD electrode leads to high electron transport and improved sensing performance. The electrochemical response of the NP-Ni/BDD electrode as a function of l-alanine concentration exhibits a linear range from 0.5 to 4.5 μM, and a detection limit of 0.01 μM at a sensitivity of 0.05 μA μM−1 cm−2 and a regression coefficient of 0.998. Furthermore, the proposed biosensor also showed high anti-interference ability, excellent stability and good reproducibility.