CAREER: Integrated Multiphoton-Phase Microscopy for Simultaneous and Correlative Imaging of Neurovascular Coupling Dynamics

Disruptions in the link between neurons and blood vessels within the brain can lead to severe neurological diseases. However, little is known about this link due to the complexity of the interaction. Current imaging techniques cannot capture this complexity at the resolution of a cell within the brain. This CAREER project aims to develop an innovative microscopy system capable of simultaneously imaging many aspects of the brain to better understand the link between neurons and blood vessels. The outcome of this project will pave the way to better understand conditions like Alzheimer’s disease and stroke. This project will also benefit society through STEM education activities aimed at strengthening the biophotonics workforce. These activities includes igniting high school students' interest in STEM, providing hands-on courses for undergraduate and graduate students, and engaging the public to raise awareness about biophotonics and STEM. The investigator’s long-term goal is to create a transformative field in fluorescence-phase multimodal imaging for simultaneous imaging of fluorescence-labeled and label-free cellular structures and functional activities in vivo. To realize this goal, the CAREER project will develop correlative, simultaneous microscopy of optical signatures (COSMOS) capable of noninvasively and concurrently recording fluorescence, second harmonic generation (SHG), and quantitative phase signals from a single dataset. Unlike current dual-contrast systems, COSMOS integrates fluorescence/SHG and phase imaging into a fully merged system. It collects two-photon excited diffracted fluorescence/SHG as multiplexed measurements, followed by computational decomposition. The reconstructed phase provides quantitative biophysical properties of neurovascular units, while the intensity of diffracted fluorescence indicates neural activity and blood dynamics, and the intensity of diffracted SHG reveals the spatial distribution of collagen in the extracellular matrix. COSMOS reconstructs multiple distinct optical signatures from the same dataset, enabling high-speed, high-throughput imaging of dynamic interactions in neurovascular units. Beyond neuroscience, COSMOS potentially has broad applications, such as studying cancer cell metastasis. 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.