Dr. Ng's research interest is in aerosol chemistry, air quality, and health effects. Her research focuses on both laboratory experiments and field measurements to understand the formation and evolution of atmospheric nanoparticles (aerosols). This research includes conducting laboratory chamber experiments in which specific compounds of interest can be isolated and studied under simple, well-controlled oxidation environments, allowing for a more detailed and direct characterization of the composition, chemical, and physical properties of aerosols. Dr. Ng is also involved in field measurement campaigns and integrated analysis of multidimensional and multiple worldwide mass spectrometer datasets to investigate the chemistry and life cycles (sources, processes, and fates) of ambient aerosols.

Dr. Ng's group also investigates the linkage between the chemical composition of atmospheric nanoparticles and their health effects. Her group uses chemical and cellular assays to study the generation of reaction oxygen and nitrogen species from exposure to particulate matter mixtures.

Additionally, she works on the development and characterization of advanced aerosol instrumentation, which can routinely characterize and monitor the mass and chemical composition of non-refractory submicron aerosols in real time.