In-situ monitoring of specific biomarkers, such as reactive oxygen species, ions, proteins (including enzyme),  at the molecular level is key to understanding their roles in physiological and pathological processes, and plays fundamental roles in early prediction of diseases treatment. Even so, tracking these ultrasmall biomolecules within body remains a challenge for researchers and clinicians due to the lack of rapid and accurate detection methods. This project aims to develop a series methods for visualization and quantification the levels of biomarkers in vivo during diseases diagnosis and treatment. A new family of responsive biosensors will be developed for the detection of these biomarkers sensitively and selectively by rational design and exploring the molecular and nanoparticle-based materials. Real-time monitoring of biomarkers within body will be quantitatively achieved by collecting the evolution of optical photons, relaxivity (MRI), and acoustic waves as the read-out signals.