EAPSI: Using nanoparticle biosensors to observe molecular DNA changes

Ruffin Sade, New York NY

Investigators

Abstract

Personalized medicine is a medical model that the healthcare community is actively striving to achieve. Related to personalized care are technologies that allow affordable and efficient access to a patient's unique molecular characteristics (i.e genetic distinctions). This research will lead to the development of a nanoparticle based biosensor which observes changes in genetic material, such as DNA, under simulated environments. Understanding the behavior of biomolecules is important in determining their functions. This research will be conducted in collaboration with Dr. Kang Wang, responsible for a dark-field microscopy system, a vital component for the proposed sensor, at Nanjing University in China. The aforementioned microscopy system is a single particle scattering spectroscopy system consisting of a dark-field microscope mounted with a spectroscopy unit and a charge-coupled device (CCD). This system can observe the scattering spectroscopy of nanoparticles. The scattering spectroscopy of these nanoparticles can vary based on biorecognition reactions and their ability to cause a change in the dielectric constant on the nanoparticle surface. The proposed research explores this phenomenon further by looking at conformational changes that occur in nanoparticle-tethered- DNA sequences under stimulated environments and determining the effects of these changes on the dielectric constant of the nanoparticle. Being able to observe a change in the dieletric constant will lead to the development of a system which characterizes conformational changes of DNA, thus a nanoprobe for detecting micro-environments in living cells that will provide greater signal intensity than conventional fluorescence probes. This system would be useful to researches looking for an analysis technique that would characterize microprocesses of several types (e.g., metabolism of cells or the corrosion of metals). This NSF EAPSI award is funded in collaboration with the Chinese Ministry of Science and Technology.