In this project co-funded by the Chemical Structure, Dynamics and Mechanisms Program-A and the Chemical Measurement and Imaging Program of the Division of Chemistry, Professor Michael Mirkin of the City University of New York, Queens College is developing new methodologies and employing them for studying electrochemical reactions on the nanoscale. Single gold nanoparticles are dispensed from a glass or carbon nanopipette and delivered precisely to the desired location on the sample surface. This methodology is useful for applications ranging from surface patterning to controlled reagent delivery to biological cells. This project will provide research opportunities to high school students and undergraduates.
The focus of the proposed research is on the combining resistive-pulse technique with the scanning electrochemical microscope (SECM) for controlled delivery of nanoparticles. The resistive-pulse setup enables monitoring of single particles passing through the pipette orifice, and the SECM is used for pipette positioning and surface patterning. The particles are immobilized on the carbon surface modified with a polyphenylene layer. The developed methodology is also employed to study the dynamics of oxidative stress in activated macrophages. Interferon-coated fluorescent nanoparticles and platinized carbon nanoelectrodes are inserted in activated macrophages and their vacuoles to characterize and quantify the reactive oxygen and nitrogen species. The broader impacts of this work include the development of useful research tools for nanotechnology and cell biology. The experiments with macrophages may help elucidate the mechanisms of oxidative stress, which are of great significance for the immune system and related diseases, including cancer.
