The presence and activity of specialized enzymes (termed proteases) are strong clues that suggest lung cancer may be present. The Bhatia lab uses aerosol medicine technology to deliver engineered, inhalable nanoprobes to investigate lung protease activity. We leverage these nano-‘detectives’ to identify and report disease states through signals released into the urine for analysis using a simple paper test – a bit like combining a home COVID test with a pregnancy test. The image, captured with an electron microscope, reveals a close-up view of these engineered nanosensors, in the form of dry powder aerosol microparticles that are compatible with point-of-care inhalers. Clinical translation of this diagnostic tool may to help alleviate surging demands and resource inequity of lung cancer detection, and provide a sensitive and easy tool to assess treatment responses and detect minimal residual disease.