A quantitative method for measuring phototoxicity of a live cell imaging microscope

Area of Science:

• Microscopy
• Cell Biology
• Biophysics

Background:

• Fluorescence imaging uses high-intensity light, posing a risk of phototoxicity to living samples.
• Phototoxicity can cause artifacts, mimicking real biological processes and compromising data integrity, especially in host-pathogen studies.
• Assessing and comparing phototoxicity across different imaging setups is crucial for experimental design.

Purpose of the Study:

• To develop a quantitative method for measuring and comparing phototoxicity in fluorescence microscopy.
• To establish a reliable metric for phototoxic damage distinct from photobleaching.
• To enable researchers to identify safe imaging parameters and avoid artifacts.

Main Methods:

• A novel methodological approach using microorganisms as biological indicators.
• Quantitative measurement of phototoxic damage across various fluorescence imaging microscopes.
• Identification of a clear phototoxicity threshold for different imaging conditions.

Main Results:

• The developed method provides a quantitative assessment of phototoxicity.
• The approach allows for the relative comparison of phototoxicity across different imaging modalities.
• A distinct threshold for phototoxic damage, separate from photobleaching, was identified.

Conclusions:

• The proposed method offers a widely applicable tool for assessing phototoxicity in fluorescence microscopy.
• This metrology of phototoxic damage helps ensure the validity of experimental observations.
• The approach is adaptable to various biological models, including mammalian cells.