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High Spatial Resolution Chemical Imaging of Implant-Associated Infections with X-ray Excited Luminescence Chemical Imaging Through Tissue
Published on: September 30, 2022
Solid-state time-gated luminescence microscope with ultraviolet light-emitting diode excitation and
Russell Connally1, James Piper
1Macquarie University, Centre for Laser Applications, Sydney, Australia 2109. rconnall@ics.mq.edu.au
Journal of Biomedical Optics
|July 8, 2008
Summary
Time-gated luminescence (TGL) effectively distinguishes long-lived fluorophores from short-lived autofluorescence. This method significantly improves signal-to-noise ratio for fluorescence microscopy applications.
Area of Science:
- Biomedical Optics
- Microscopy Techniques
- Fluorescence Spectroscopy
Background:
- Autofluorescence in natural materials complicates fluorescence-based detection.
- Discrimination of fluorophores is challenging due to overlapping emission spectra.
- Fluorescence decay lifetime offers a temporal domain for distinguishing signals.
Purpose of the Study:
- To evaluate time-gated luminescence (TGL) for discriminating specific fluorophores from autofluorescence.
- To demonstrate the utility of TGL in enhancing signal-to-noise ratio (SNR) in microscopy.
- To analyze Giardia lamblia cysts using TGL microscopy.
Main Methods:
- Utilized a high-power UV LED as an excitation source on an Olympus BX51 microscope.
- Employed an electron-multiplying CCD (EM-CCD) camera synchronized with the excitation pulse for time-gated detection.
- Applied TGL to image Giardia lamblia cysts labeled with BHHST against an autofluorescent background.
Main Results:
- Captured useful TGL images in real-time with a single exposure cycle.
- Achieved a 30-fold improvement in SNR using TGL compared to conventional fluorescence microscopy.
- Demonstrated successful discrimination of BHHST-labeled cysts from autofluorescence.
Conclusions:
- TGL is a powerful technique for overcoming autofluorescence limitations in microscopy.
- The developed TGL system provides significant SNR enhancement for biological sample analysis.
- TGL microscopy offers a viable solution for improved detection sensitivity in challenging fluorescent environments.
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