Correlative imaging to resolve molecular structures in individual cells: Substrate validation study for...

Area of Science:

• Biomedical Optics
• Chemical Imaging
• Cellular Biology

Background:

• Light microscopy provides high-resolution imaging but lacks chemical specificity.
• Optical photothermal infrared microspectroscopy (O-PTIR) enables sub-micron chemical information extraction.
• Substrate chemistry can influence infrared spectral data in microspectroscopy.

Purpose of the Study:

• To investigate the applicability of sub-micron infrared microspectroscopy for biomedical applications.
• To analyze the impact of substrate chemistry on infrared spectra of individual neurons.
• To demonstrate correlative immunofluorescence and O-PTIR imaging for subcellular molecular analysis.

Main Methods:

• Cultured individual neurons on various imaging substrates.
• Acquired infrared spectra using optical photothermal infrared microspectroscopy (O-PTIR).
• Utilized immunofluorescence to locate specific organelles for targeted O-PTIR measurements.

Main Results:

• Substrate chemistry significantly contributes to the infrared spectra of neurons.
• O-PTIR successfully extracted chemical information from individual neurons at sub-micron resolution.
• Correlative immunofluorescence/O-PTIR imaging allowed direct visualization of molecular structures within subcellular compartments.

Conclusions:

• Sub-micron infrared microspectroscopy, particularly O-PTIR, is a powerful tool for chemical imaging in biomedical research.
• Understanding substrate contributions is crucial for accurate O-PTIR spectral interpretation.
• Correlative O-PTIR imaging enhances cellular analysis by combining molecular specificity with subcellular localization.