Axial Scanning Metal-Induced Energy Transfer Microscopy for Extended Range Nanometer-Sectioning Cell Imaging

Area of Science:

• Biomedical Optics
• Cellular Imaging
• Nanotechnology

Background:

• Nanometer-sectioning optical microscopy is vital for membrane studies.
• Existing methods like MIET imaging have limited measurement ranges (<100 nm).
• These limitations hinder the study of thicker cellular structures, such as lamellipodia.

Purpose of the Study:

• To develop an optical imaging scheme for precise axial localization of multiple molecular layers.
• To extend the measurement range for nanometer-scale thickness determination.
• To overcome the limitations of current microscopy techniques in studying cellular structures.

Main Methods:

• Utilized metal-induced energy transfer (MIET) imaging.
• Incorporated axial focal plane scanning.
• Employed biexponential analysis within fluorescence lifetime imaging microscopy.

Main Results:

• Successfully identified axial locations of two molecular layers with extended range and nanometer precision.
• Demonstrated feasibility using an artificial sample with a known structure.
• Measured human aortic endothelial cell lamellipodia thickness (100-450 nm) with 18.3 nm precision.

Conclusions:

• The proposed optical imaging scheme accurately measures the thickness of cellular structures.
• This method significantly improves upon existing nanometer-sectioning microscopy techniques.
• Offers enhanced capabilities for in-depth biomedical studies of cellular membranes and structures.