The goal of this preliminary study was to produce a promising alternative tool for the direct, rapid and
specific determination of vitamin C (VC) content in real samples of different agricultural crops without
pre-treatment. For this purpose, a VC electrochemical biosensor based on one-step immobilization of
ascorbate oxidase in the biocompatible conducting poly(3,4-ethylenedioxythiophene)-lauroylsarcosinate
(PEDOT-SL) film was facilely developed. AO molecules were incorporated into the resulting PEDOT-SL film
by using a co-electrodeposition technique under optimum conditions. The sodium N-lauroylsarcosinate
provided a good biocompatible environment for biologically-active macromolecules AO. The electrochemical
characterization and scanning electron microscopy indicated that AO molecules were successfully
immobilized in this PEDOT-SL film. The parameters of the biosensor such as the film thickness, working
potential, pH, concentration of PBS, and temperature were optimized. The biosensor displayed an excellent
bioelectrocatalytic activity to the oxidation of VC and could successfully detect VC in the concentration
range of 0.002–14 mM. The biosensor also exhibited a high sensitivity of 80.4 mA M1 cm2, a fast
response time of 15 s, a low working potential of 0.2 V, a low detection limit of 0.464 lM. In addition, high
bioaffinity, bioactivity, stability and specificity of this biosensor were also evaluated. The excellent performance
of the prepared biosensor and good results of the VC determination in commercial juices and vegetable
crops indicated that the as-fabricated biosensor will be a good candidate for the detection and
analysis of VC in agricultural crops.