Electrochemical immunoassay for the detection of stress biomarkers

Jwan O Abdulsattar; Gillian M Greenway; Jay D Wadhawan

doi:10.1016/j.heliyon.2020.e03558

Electrochemical immunoassay for the detection of stress biomarkers

Heliyon. 2020 Mar 18;6(3):e03558. doi: 10.1016/j.heliyon.2020.e03558. eCollection 2020 Mar.

Authors

Jwan O Abdulsattar¹, Gillian M Greenway², Jay D Wadhawan³

Affiliations

¹ Department of Chemistry, College of Science, Mustansiriyah University, Baghdad, Iraq.
² Department of Chemistry and Biochemistry, University of Hull, Cottingham Road, Hull, HU6 7RX, UK.
³ Department of Chemical Engineering, University of Hull, Cottingham Road, Hull, HU6 7RX, UK.

Abstract

A rapid electrochemical immunoassay method was developed to detect and measure stress biomarkers (cortisol and cortisone) in two biological samples (Zebrafish whole-body and artificial saliva). This methodology utilizes an immunoassay approach taking advantage of the lock and key mechanism that is related to the antibody-antigen interaction depending on the reliable immobilization of the antibody labelled with ferrocene tags (Ab-Fc) on a modified tin-doped indium oxide (ITO) electrode using electrochemical instrumentation to build a POC platform. The limit of detection (LOD) obtained for this biosensor was 1.03 pg ml^-1 for cortisol and 0.68 pg ml^-1 for cortisone, respectively. The correlation coefficient was 0.9852 and 0.9841 for cortisol and cortisone, respectively with a linear concentration from (0-50 ng ml^-1) which covers the standard levels of stress hormones in both selected biological samples. The incubation time was investigated and 30 min was found to be the optimum incubation time. This time would be acceptable for the POC system as total process time can be determined within 35 min.

Keywords: Biomedical engineering; Biosensors; Electrochemistry; Immunoassay; Point of care; Stress biomarkers.