Verification of cell viability at progressively higher scanning forces using a hybrid atomic force and fluorescence...

Area of Science:

• Live cell imaging
• Atomic Force Microscopy
• Cell Biology

Background:

• Atomic Force Microscopy (AFM) is a powerful tool for live cell imaging.
• Ensuring cell viability during AFM scanning is crucial for supra-vital applications.
• Previous studies have not established clear force guidelines for different cell types.

Purpose of the Study:

• To determine the impact of AFM contact mode scanning forces on cell viability.
• To establish safe force ranges for AFM imaging of commonly cultured cell lines.
• To provide guidelines for the prudent use of AFM as a live cell imaging tool.

Main Methods:

• Utilized complementary optical techniques with fluorescent dyes (rhodamine-123 and ethidium homodimer) to assess cell viability.
• Applied increasing loads in contact mode using an atomic force microscope.
• Tested five distinct cell lines: human squamous carcinoma (A431), fibroblast, HeLa, Potorous tridactylis (PtK2), and rat intestinal epithelial (RIE).

Main Results:

• Quantified cell viability before and after atomic force microscope scanning under varying force loads.
• Identified specific force ranges that maintain viability for each of the five tested cell lines.
• Demonstrated the effectiveness of rhodamine-123 and ethidium homodimer assays in assessing AFM-induced cellular damage.

Conclusions:

• Established critical force ranges for the safe application of atomic force microscopy in live cell imaging.
• Provided essential guidelines for researchers using AFM on human squamous carcinoma (A431), fibroblast, HeLa, PtK2, and RIE cells.
• Highlighted the importance of pre- and post-scanning viability assessments for supra-vital AFM studies.