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Compact 3D printed module for fluorescence and label-free imaging using evanescent excitation
Vikas Pandey1, Shalini Gupta1, Ravikrishnan Elangovan2
1Department of Chemical Engineering, Indian Institute of Technology, Delhi, 110016, India.
Methods and Applications in Fluorescence
|October 28, 2017
Summary
A new compact module, cTIRF, enables total internal reflection fluorescence (TIRF) microscopy on any microscope. This cost-effective approach enhances signal-to-noise ratio for imaging fluorophores and label-free nanoscale objects.
Area of Science:
- Biophysics
- Optical Microscopy
- Nanotechnology
Background:
- Total internal reflection fluorescence (TIRF) microscopy offers high resolution and vertical confinement near interfaces.
- Traditional TIRF microscopy requires specialized high numerical aperture objectives, limiting imaging area and increasing costs.
- Existing methods face limitations in cost, flexibility, and imaging area.
Purpose of the Study:
- To develop a compact, versatile, and cost-effective module for TIRF microscopy.
- To enable high signal-to-noise ratio (SNR) imaging of fluorophores and label-free nanoscale objects.
- To adapt existing optical microscopes for TIRF capabilities without expensive components.
Main Methods:
- Development of a compact 3D module (cTIRF) for planar waveguide illumination.
- Integration of the cTIRF module as a fixture to standard optical microscopes.
- Utilizing perpendicular incidence optics for label-free evanescent scattering imaging.
Main Results:
- The cTIRF module successfully generates evanescent waves on microscope glass slides.
- High SNR fluorescence imaging was achieved using any magnification objective.
- Label-free imaging of submicron objects (latex beads, mammalian cells) demonstrated enhanced SNR without emission filters.
Conclusions:
- The cTIRF module provides a flexible and affordable solution for TIRF microscopy.
- This approach significantly improves SNR for both fluorescence and label-free imaging.
- The technology is scalable and suitable for resource-limited settings.
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