Barhoumi Lassaad*, Ben Ali Mounir
University of Sousse, Tunisia
Title: A novel chronoamperometric immunosensor for rapid detection of cytokine TNF-α in human saliva
Biography
Biography: Barhoumi Lassaad*, Ben Ali Mounir
Abstract
We report in this work, the synthesis and characterization of a novel immunosensor based a screen-printed gold electrode (SPAuE) modified with a new structure of iron magnetic nanoparticles coated with poly (pyrrole-co-pyrrole-2-carboxylic acid, Py-Py-COOH) (Py/Py-COOH/MNP) [1] particles to increase the immunosensor sensitivity of Tumor Necrosis Factor-α (TNF-α) [2, 3]. TNF-α antibodies were covalently bonded to Py/Py-COOH/MNP modified SPEAu. A sandwich-type detection strategy was then employed for antigen (Ag-TNF-α) detection through the labeled conjugate antibody (Ab-TNF-α-HRP) activity in a TMB solution [4]. Finally, the chronoamperometry technique was applied to characterize the modified SPEAu. The use of a conjugate antibody anti-TNF-α labeled with horseradish peroxidase (Ab-TNF-α-HRP) was investigated using tetramethylbenzidine (TMB) substrate as electrochemical substrate. The modified screen-printed gold electrode (SPEAu) was characterized for the first time, using atomic force microscopic (AFM) and scanning electron microscopy (SEM). The specificity of the immune-sensor was then investigated under the optimal experimental conditions by analyzing aqueous solutions containing possible interferences represented by other salivary cytokines secreted in the acute stage of inflammation [5], such as interleukin-6 (IL-6) and interleukin-10 (IL-10). The developed immune-sensor showed good performances for Ag-TNF-α detection within the range of 1 pg mL-1 to 15 pg mL- 1 of antigen TNF-α was determined at 1 pg mL-1. The present immune-sensor is this very promising for sensitive and rapid detection of antigen Ag-TNF-α in clinical sample.