Label-Free Electrochemical Immunosensor Based on Ionic Liquid Containing Dialdehyde As a Novel Linking Agent for the Antibody Immobilization

Abstract

Demand for label-free electrochemical immunosensor has resulted in extensive research in improving the conductivity of a sensing interface and antibody immobilization. In this paper, an electrochemical immunosensor for prostate specific antigen based on dialdehyde-functionalized ionic liquid used as a novel linking reagent to replace glutaraldehyde for the antibody immobilization is described. The novel linking reagent enhanced the conductivity of the sensing interface. Thus, the proposed immunosensor had a wider linear range of 0.05-30 ng mL-1, with a lower detection limit of 0.04 ng mL-1 compared with the immunosensor based on glutaraldehyde for the antibody immobilization.