The broader impact/commercial potential of this I-Corps project is the development of reliable rapid screening for COVID-19. The global COVID-19 diagnostics market is expanding rapidly. The market size is valued at $19.8 billion in 2020 and is expected to grow at a compound annual growth rate (CAGR) of 3.1% from 2021 to 2027. Compared to the existing smell tests, the proposed technology facilitates remote-controlled switching capacity of multiple odor molecules and instant auto-evaluation. The proposed device allows standardized emission of multiple odor molecules using a single device. Moreover, results from the device may be delivered directly through the app or over the web enabling testing in telemedicine settings. Since there is no reliable testing for rapid diagnosis of asymptomatic and presymptomatic COVID-19 cases, this technology may potentially change the paradigm of diagnosis.This I-Corps project is based on the development of a nanoparticle-based smell test device. The proposed nanoparticle-based system triggers the controlled release of specific molecules on demand. This smell test device has potential application in the diagnosis of diseases affecting the sense of smell. Since an impaired sense of smell is a distinct sign of COVID-19 in both asymptomatic and presymptomatic cases, this technology has the potential for screening and early diagnosis of the disease. Moreover, unlike traditional smell tests, the proposed technology is designed such that it may be configured into any form factor from a plate to a pen to incorporation in an inhalation device. This technique allows quantitative control of multiple scent intensities facilitating a new layer of detailed data that has hereto not been available. Understanding the impact of COVID-19 in olfaction will open new doors in diagnosis and disease management.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.