Analytical & Bioanalytical Techniques

Biography

Biography: Tianyu Zheng

Abstract

Dynamic light scattering (DLS) is an analytical technique used routinely to measure the hydrodynamic sizes of particles with diameters in the nanometer region. Gold nanoparticles are known for their exceptional light scattering properties. By combining the strong light scattering property of gold nanoparticle probes with the size measurement capability of DLS, a new technique named as D2Dx (from diameter to diagnostics) for chemical and biological target detection and analysis was developed. Gold nanoparticles can be surface-modified with various chemical ligands, antibodies or other binding molecules to form gold nanoparticle probes. The binding of chemical or biological target analytes with their specific gold nanoparticle probes can lead to nanoparticle cluster formation, and subsequently, an average particle size increase of the assay solution. Such particle size increases can be measured by DLS, and correlated to the quantity of the target analytes. D2Dx is a single-step homogeneous solution assay, easy to perform, of low cost, and has excellent sensitivity and reproducibility. So far, this technique has been applied successfully for quantitative detection and analysis of a wide range of chemical and biological targets, including proteins, DNAs, viruses, carbohydrates, small chemicals, toxic metal ions, food and environmental toxins. In this talk, I will explain the principle of D2Dx, give an overview on the application potentials of this technique in biomedical research, food safety and environmental protection, and then present several specific examples of using D2Dx for protein detection and analysis.