Scanning probe microscopy

Area of Science:

• Biophysics
• Nanotechnology
• Molecular Biology

Background:

• Scanning probe microscopy, especially atomic force microscopy (AFM), has gained significant traction in biological sciences.
• The technique is transitioning from qualitative imaging to quantitative analysis of biomolecules and cells.
• Future applications include microinstrument development for process control and sensing.

Purpose of the Study:

• To review recent advances in AFM instrumentation and methods for biological applications.
• To highlight the evolving capabilities of AFM in studying biomolecular dimensions, properties, and interactions.
• To showcase emerging applications in biosensing and structural biology.

Main Methods:

• Atomic Force Microscopy (AFM) with a focus on tapping mode operation, including its adaptation for liquid environments.
• Cryo-AFM for high-resolution imaging of biological molecules at low temperatures.
• Force spectroscopy techniques to measure molecular recognition forces.

Main Results:

• Tapping mode AFM is increasingly preferred for imaging biological molecules, with successful implementation in liquid.
• Cryo-AFM offers improved resolution for biological samples.
• AFM enables precise measurements of viscoelastic properties and molecular recognition forces, leading to novel biosensor concepts.
• Structural studies include DNA mapping, imaging transcription, and analyzing drug-DNA interactions.

Conclusions:

• AFM is a versatile tool rapidly advancing in biological research, offering quantitative insights into molecular structure and function.
• Ongoing developments in AFM instrumentation and methods are expanding its utility in biophysics, nanotechnology, and molecular biology.
• AFM is poised for further evolution into sophisticated microinstruments for advanced sensing and process control applications in life sciences.