Natural products offer excellent sources of health-promoting medicines yet challenges in efficiently and economically sourcing these value-add bio-compounds have prevented their greater availability and promotion to public health. We address this problem by developing a novel image-based screening technology that offers highly sensitive, phenotypic bioassays of metabolite concentrations on live single cells. This allows a greatly improved method for identification of better natural product producers, as well as quantitative information about the production per cell and production distribution across the population. This high-resolution, non- destructive, label-free cell screening and cell sorting system is based on vibrational photothermal microscopy which uses mid-infrared light to probe molecular vibrational absorptions at resolutions comparable to visible light microscopes. To demonstrate the utility of the approach we focus on the production of essential polyunsaturated fatty acids (PUFAs) in lipid droplets sourced from microalgae (thraustochytrids) â a natural producer of PUFAs. These long-chain fatty acids play a vital role in the physiological health of cells and tissues throughout the body are commercialized as a prominent nutraceutical. To develop enriched cell lines, we will engineer and prototype a multichannel microfluidic chip with an active piezoelectric actuator to selectively save cells identified through photothermal as being highly productive. Our goal is to provide an attractive method to non-destructively evaluate metabolite content in engineered microbes including bacteria and yeast, not just algae, and for a variety of high-value metabolites. To accomplish these goals, we have established a team of qualified experts including specialists in advanced microscopy, microfluidics design, and algae cultivation for industrial applications. Ultimately, the methods developed here will showcase a roadmap toward rare-cell discovery and active cell sorting based on chemical mapping allowed through the photothermal imaging contrast.
Public Health Relevance Statement: Project Narrative. Development of a broadly tunable mid-infrared light source with high pulse energy and narrow linewidth is essential to generate strong signals through vibrational photothermal imaging. Such an optimized light source would bring this nascent imaging modality to the forefront of biomedical imaging of single-cells and tissue biopsies by enabling true chemical mapping at much higher throughput than methods reliant on legacy IR light sources. Here, to support such innovation, we unite a team of expert microscopists and laser development researchers to prototype and characterize performance of such a light source for the purpose of generating high-resolution, hyperspectral data cubes with chemical information throughout the IR-fingerprint region.
Project Terms: absorption; Algae; Back; Dorsum; Bacteria; Biological Assay; Assay; Bioassay; Biologic Assays; Biology; Biopsy; Malignant Neoplasms; Cancers; Malignant Tumor; malignancy; neoplasm/cancer; Cell Line; CellLine; Strains Cell Lines; cultured cell line; Cell Separation; Cell Isolation; Cell Segregation; Cell Separation Technology; cell sorting; Cells; Cell Body; Comparative Study; Complement; Complement Proteins; Engineering; Fingerprint; Germanium; Goals; Health; Health Promotion; Salutogenesis; promoting health; Heating; Industrialization; Lasers; Laser Electromagnetic; Laser Radiation; Light; Photoradiation; Lipids; Maps; Medicine; Methods; Microscopy; Molecular Probes; Noise; Optics; optical; Pain; Painful; Phenotype; Play; Polyunsaturated Fatty Acids; Production; Productivity; Public Health; Refractive Indices; Research; Research Personnel; Investigators; Researchers; Role; social role; Science; Signal Transduction; Cell Communication and Signaling; Cell Signaling; Intracellular Communication and Signaling; Signal Transduction Systems; Signaling; biological signal transduction; Spectrum Analysis; Spectroscopy; Spectrum Analyses; Technology; Tissues; Body Tissues; Yeasts; Zinc; Zn element; Imaging Techniques; Imaging Procedures; Imaging Technics; Specialist; detector; Label; Pump; improved; Microscopic; Physiologic; Physiological; Chemicals; Visible Light; Visible Light Radiation; Visible Radiation; Fourier Transform; Morphology; tool; Diagnostic; Specimen; Research Specimen; Physiologic pulse; Pulse; Cellular biology; cell biology; light microscopy; Protocols documentation; Protocol; Source; Techniques; System; Light Microscope; long chain fatty acid; infrared microscopy; Performance; Histopathology; Speed; novel; Sampling; µfluidic; Microfluidics; image-based method; imaging method; imaging modality; preventing; prevent; Address; Microfluidic Microchips; Microfluidic Device; Microfluidic Lab-On-A-Chip; microfluidic chip; Dark-Field Microscope; Data; Molecular Profiling; Molecular Fingerprinting; molecular profile; molecular signature; Predictive Value; Qualifying; Resolution; resolutions; Nutraceutical; Tissue Microarray; Tissue Arrays; Tissue Chip; Mammary Gland Parenchyma; Breast Tissue; Mammary Gland Tissue; Process; Development; developmental; Image; imaging; designing; design; sub micron; submicron; quantum; Population; innovate; innovative; innovation; Microbe; fundamental research; prototype; commercialization; lenses; lens; high standard; screenings; screening; contrast imaging; naturally occurring product; Natural Products; Tissue imaging; experiment; experimental research; experiments; experimental study; imaging based approach; imaging approach; Visualization; Rapid screening; detection limit; biomedical imagi