Studies On Nanoparticles-based Novel DNA And Immuno Electrochemical Biosensors

Electrochemical biosensor is a novel and developing technique that linking biochemical, electrochemical and electronic techniques together with the advantages of being simple, reliable, sensitive and selective for biomolecule detection. To prepare electrochemical biosensors, the immobilization of the biomolecule should be a key factor in sensor design and construction. This dissertation focuses on designing and fabricating novel biomimetic interface combining some kinds of nanoparticles with bifunctional sol-gel, conducting polymer and polycation for the immobilization of biomolecules. Atomic force microscopy, UV-Vis spectra and electrochemical techniques are used as tools for studying the properties of interface. We also explore the electrochemical impedance spectroscopy (EIS) as a platform for indicator free DNA and immuno sensing assay. The dissertation includes two parts:Part I of the dissertation are our research focused on the fabrication of novel nanoparticles-based electrochemical DNA biosensors.1. The DNA biosensor has been developed via Ag nanoparticles and bilayer two-dimensional MPTS sol-gel network. And we utilized the EIS as a platform for DNA sensing assay.2. We explored EIS as a platform for indicator free DNA sensing assay via Au nanoparticles and MPTS. After hybridization, an obvious decrease of impedance values was observed in phosphate buffer, because of the higher conductivity properties of dsDNA compared to ssDNA.3. A novel immobilization strategy combining opposite-charged adsorption and nanocomposite...