Molecular Imaging of Cells Likely with New Take on Atomic Force Microscopy

July 17, 2006

A seminal early event in the history of nanotechnology was the development of the atomic force microscope (AFM), which used a nanoscale cantilever to image solid materials at the atomic level.

The insights gained from AFM studies provided a dramatic increase in our understanding of materials at the nanoscale, and while atomic force microscopy has been used in biomedical research, its applicability in biomedical research has been limited by the fact that AFM does not work well in water.

Now, a team of investigators at Oak Ridge National Laboratory, led by Sergei Kalinin, Ph.D., have developed what it calls piezoresponse force microscopy, or PFM. This new approach to molecular-scale imaging relies on the piezoelectric phenomenon that translates electrical energy into mechanical movement in certain types of materials. Quartz crystals, as well as many biological polymers, such as enzymes and DNA, have the ability to generate piezoelectric responses. The researchers report their work in the journal Physical Review Letters.

The new technique uses an AFM microscope modified so that its gold-coated nanoscale cantilever tip is suspended in water just above the surface of a piezoelectric material, such as a quartz crystal. Applying an electric current to the piezoelectric material causes it to move, a event registered by the AFM tip. Using this approach, the researchers achieved an imaging resolution of 3 nanometers. They note that the inherent piezoresponsive nature many biological materials exhibit should allow future imaging of biological structures and their movements under physiological conditions.

This work is detailed in a paper titled, “High resolution electromechanical imaging of ferroelectric materials in a liquid environment by piezoresponse force microscopy.” An abstract of this paper is available through PubMed.

Source: National Cancer Institute

Explore further: How to tell when a nanoparticle is out of shape

Related Stories

How to tell when a nanoparticle is out of shape

December 21, 2016

Nanoparticles—those with diameters less than one-thousandth the width of a human hair—are increasingly prevalent in high technology, medicine, and consumer goods. Their characteristics, both desirable and undesirable, ...

New highly sensitive AFM revolutionizes nano imaging

February 9, 2006

While a microphone is useful for many things, you probably wouldn't guess that it could help make movies of molecules or measure physical and chemical properties of a material at the nanoscale with just one poke.

Recommended for you

New low-cost technique converts bulk alloys to oxide nanowires

January 19, 2017

A simple technique for producing oxide nanowires directly from bulk materials could dramatically lower the cost of producing the one-dimensional (1D) nanostructures. That could open the door for a broad range of uses in lightweight ...

Creating atomic scale nanoribbons

January 19, 2017

Silicon crystals are the semiconductors most commonly used to make transistors, which are critical electronic components used to carry out logic operations in computing. However, as faster and more powerful processors are ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.