Fabrication of Flexible Arrayed Lactate Biosensor Based on Immobilizing LDH-NAD+ on NiO Film Modified by GO and MBs

We proposed the flexible arrayed lactate biosensor based on immobilizing L- lactate dehydrogenase ( LDH) and nicotinamide adenine dinucleotide ( NAD +) on nickel oxide ( NiO) film, and which the average sensitivity could be enhanced by using graphene oxide ( GO) and magnetic beads ( MBs). By using GO and MBs, it exhibits excellent sensitivity ( 45.397 mV/ mM) with a linearity of 0.992 in a range of 0.2 mM to 3 mM. According to the results of electrochemical impedance spectroscopy ( EIS), the electron transfer resistance of LDH- NAD + - MBs/ GPTS/ GO/ NiO film was smaller than those of LDH- NAD+/ GPTS/ GO/ NiO film and LDH- NAD + / GPTS/ NiO film, and it presented the outstanding electron transfer ability. After that, the limit of detection, anti- interference effect and bending test were also investigated.