Development of electrochemical biosensor with ceria-PANI core-shell nano-interface for the detection of histamine

A mediator-free electrochemical biosensor with CeO2-PANI nano-interface for sensing histamine using diamine oxidase (DAO) has been developed. CeO2-PANI core-shell nanoparticles were prepared by hydrothermal method. The field emission scanning electron microscopy (FE-SEM) revealed the aggregated spherical morphology of CeO2. The core-shell formation of CeO2-PANI was confirmed with field emission transmission microscopy (FE-TEM). The polycrystallinity of CeO2 and CeO2-PANI was confirmed using X-ray diffraction (XRD). Immobilization of DAO with CeO2-PANI was confirmed with Fourier transform infrared spectroscopy (FT-IR). Electrochemical studies were carried out through cyclic voltammetry and amperometry using modified GCE/CeO2-PANI/DAO as a working electrode, Ag/AgCl saturated with 0.1 M KCl as a reference electrode and platinum (Pt) wire as a counter electrode. The linear range was observed from 0.45 to 1.05 mM with a sensitivity of 724.94 μA cm−2 mM−1. Michaelis-Menten constant was calculated as 0.798 mM. It exhibited limit of detection of 48.7 μM, limit of quantification of 132.4 μM with a response time of <1 s and good shelf life of 86% till 18 days. Also the developed biosensor was applied on tiger prawn to estimate the histamine content.