Flexible immunosensor for cortisol detection in non-invasive saliva samples

• Grant number: 17/15605-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2017
• End date: November 30, 2018
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Osvaldo Novais de Oliveira Junior
• Grantee: Felipe Gabriel Pereira
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated research grant: 13/14262-7 - Nanostructured films from biologically-relevant materials, AP.TEM

Abstract

This Project is aimed at developing and characterizing flexible devices functionalized with self assembled monolayers (SAM) to prepare the surface for immobilization of antibody anti-cortisol. All steps, from preparation to detection, will be studied by electrochemical techniques (cyclic voltammetry, electrochemical impedance spectroscopy), in addition to atomic force microscopy (AFM) and scanning electron microscopy (SEM). In a second step, the gold nanostructures will be coated with self-assembed monolayers (SAMs) of alkanethiol (mercaptoacetic acid and 11-mercaptoundecanoic) to prepare the surface for immobilization of biomolecules, such as enzymes, antibodies and DNA. This coating will be analyzed using electrochemical techniques (voltammetry, amperometry, electrochemical impedance spectroscopy), contact angle measurements and infrared reflection-absorption with modulated polarization (PM-IRRAS). Detection will be conducted with cortisol adsorption in the functionalized surface with antibodies and electrochemical techniques (voltammetry, amperometry, electrochemical impedance spectroscopy) in standard solutions. The imunosensors will also be used for detecting cortisol in saliva non-invasive samples. (AU)