Design and fabrication of nanostructured flexible devices for biomarkers detection

Abstract

This Project is aimed at developing and characterizing flexible devices made of gold nanostructures obtained via photolithography on a platinum surface. These nanostructured flexible surfaces will be characterized by electrochemical techniques (cyclic voltammetry, electrochemical impedance spectroscopy), in addition to atomic force microscopy (AFM) and scanning electron microscopy (SEM), to determine the size and distribution of the gold nanostructures as well as the exposed area of platinum. With the considerable increase in area of the electroactive surfaces, the electrocatalytic activity of the nanostructured flexible device should be sufficient to detect biomarkers, as well as uric acid, ascorbic acid, dopamine and NADH. 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), and infrared reflection-absorption with modulated polarization (PM-IRRAS). Detection will be conducted with electrochemical techniques in standard solutions. The biosensors will also be used for detecting lactate and cholesterol in sweat by applying the flexible devices directly onto the skin during physical activities, while detection of glucose and cortisol will be performed in saliva, thus avoiding invasive methods. The immunosensors and genosensors will be used for detection of head and neck cancer at early stages. (AU)