Active-sensing Spectral Fluorescence Lifetime Imager

Plant metabolism is a key biological process that involves intricate physiological and chemical processes to synthesize and convert substances into energy. Fully understanding the metabolic processes requires capable imaging technology to visualize the spatiotemporal dynamics and transport of key metabolites at the cellular and molecular levels. Nonetheless, plant biologists lack a critical non-destructive imaging tool that provides high spatiotemporal resolution to tackle this problem. While advanced microscopy and spectroscopy instruments are available for use in laboratory settings for studies of biochemical processes in plants and microbial communities, those often require destructive sample preparations and are not suited for field use, limiting the value to a broader scientific community. A field-deployable hyperspectral confocal fluorescence lifetime imager is proposed to enable non-destructive functional imaging of metabolism and physiological and biochemical responses of plants and microbes. This imager will measure sub-cellular level, confocal optical sectioned, and spectral discriminated fluorescence lifetime images of plant systems in vivo, providing important new information on the spatiotemporal distributions and dynamics of key metabolites in plant systems. Technology innovations including random-access imaging, computational spectroscopy, and high-speed lifetime measurements are employed, which enable high throughput, multi-dimensional imaging based on a simple, robust, and field-deployable hardware platform. A prototype hyperspectral confocal fluorescence lifetime imager was developed and characterized. High-resolution fluorescence images of a variety of plant tissues with spectral and lifetime discrimination capability were acquired using the prototype instrument, demonstrating the feasibility of the proposed approaches. Based on the Phase I feedback from the plant biologists, an upgraded Phase II prototype instrument has been designed, and a Phase II research plan has been developed. Two prototype hyperspectral confocal fluorescence lifetime imagers will be fabricated, refined, and tested at two institutes with research activities focused on plant biology. The Phase II instrument incorporates additional technical innovations and improved compactness, robustness, and improved performance. The testing results will be disseminated through conferences and journal publications to increase the awareness of potential customers. A plan for technology commercialization will be implemented. The Phase II instrument will be compact, low-cost, and field-deployable, facilitating the real-time assessment of plant metabolism and the physiological and biochemical interactions between plants and microbes. This imager will enable plant biologists to conduct a wide range of advanced research investigations in the plant and microbial communities. The initial target customers will be academic researchers quickly followed by large agri-business and biofuel companies.