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Fluorescence Lifetime Macro Imager for Biomedical Applications
Published on: April 7, 2023
Compact flashlamp-based fluorescence imager for use under ambient-light conditions
Frederick Lanni1, David A Pane, Shmuel J Weinstein
1Molecular Biosensor and Imaging Center and Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
The Review of Scientific Instruments
|April 7, 2007
Summary
A new low-power, lightweight fluorescence imager for autonomous rovers can detect faint biological signals in extreme environments. This instrument uses pulsed xenon flashlamps and digital image processing to overcome ambient light interference, enabling sensitive detection of biomolecules.
Area of Science:
- * Astrobiology and Planetary Science
- * Remote Sensing and Imaging Technology
Background:
- * Autonomous vehicles require sophisticated sensors for in-situ environmental analysis.
- * Detecting biological signatures in extreme environments presents significant challenges due to low signal levels and ambient light interference.
Purpose of the Study:
- * To develop a low-power, lightweight, multiwavelength fluorescence imager for autonomous rover applications.
- * To enable sensitive detection of biological molecules and autofluorescence in extreme terrestrial environments.
Main Methods:
- * Utilized a compact xenon flashlamp, bandpass filters, and a gated charge-coupled device camera.
- * Implemented microsecond excitation pulses, synchronized camera operation, and digital image subtraction to reject ambient light.
- * Incorporated excitation (380-600 nm) and emission (460-740 nm) filters for various biomolecule detection, plus RGB filters for true-color imaging.
- * Developed automated focusing based on R-band imaging prior to fluorescence acquisition.
Main Results:
- * Achieved quantification of weak fluorescence (0.05 pmol fluorescein/mm²) against a shaded sunlight equivalent background.
- * Demonstrated capability for detecting chlorophyll, protein, DNA, lipid, carbohydrate stains, and autofluorescence.
- * Successfully acquired true-color images using RGB filters and white-light flashes.
Conclusions:
- * The developed fluorescence imager is suitable for autonomous detection of organisms and biomolecules in extreme environments like desert soils.
- * The system's ability to discriminate against ambient light and quantify weak fluorescence makes it a valuable tool for astrobiological exploration.
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