A Semi-Automated Positioning System for contact-mode Atomic Force Microscopy (AFM).

Area of Science:

• Biophysics
• Biomedical Engineering
• Materials Science

Background:

• Contact mode Atomic Force Microscopy (CM-AFM) is crucial for studying cell and tissue mechanics.
• Spatially heterogeneous tissue sampling and multi-magnification registration pose significant challenges for AFM experiments.
• Current AFM methods are often laborious and time-consuming for tissue analysis.

Purpose of the Study:

• To develop an automated, image-guided micropositioning system for AFM indentation on human breast tissue.
• To enhance the efficiency and accuracy of AFM-based mechanical property measurements in complex biological specimens.
• To overcome limitations in tissue registration and probe alignment across multiple magnifications.

Main Methods:

• Development of an image-guided micropositioning system for automated alignment of AFM probes and tissue samples.
• Utilizing digital stained images annotated by a pathologist to identify Regions of Interest (ROI).
• Integration of a positioning system to guide unstained tissue placement relative to the AFM probe tip.

Main Results:

• The developed system automates the alignment of AFM probes and human breast tissue cores across magnifications.
• Significant reduction in the operating time for AFM indentation experiments was achieved.
• The system demonstrated improved efficiency for mechanical property analysis of heterogeneous tissue samples.

Conclusions:

• The image-guided micropositioning system considerably improves the efficiency of AFM indentation experiments on human breast tissue.
• This automated approach is a viable supplement to commercial AFM stages, particularly those with limited range.
• The technology facilitates more precise and rapid mechanical characterization of complex biological tissues.