Microscopy method with femtogram accuracy delves into cell growth

Aug. 26, 2011
Looking to discover whether cells grow at a constant rate or exponentially, a research team from the University of Illinois developed an imaging method called spatial light interference microscopy (SLIM) that can measure cell mass using two beams of light.

Looking to discover whether cells grow at a constant rate or exponentially, a research team from the University of Illinois (Champaign, IL) developed an imaging method called spatial light interference microscopy (SLIM) that can measure cell mass using two beams of light.

An extremely sensitive method, SLIM can quantitatively measure mass with femtogram accuracy; by comparison, a micron-sized droplet of water weighs 1,000 fg. It can measure the growth of a single cell and even mass transport within the cell for bacteria, mammalian cells, adherent cells, nonadherent cells, single cells and populations, says Mustafa Mir, a graduate student and a first author of the paper.

SLIM, which combines phase-contrast microscopy and holography, does not require staining or any other special preparation. The noninvasive method uses white light and can be combined with more traditional microscopy techniques, such as fluorescence, to monitor cells as they grow.

“We were able to combine more traditional methods with our method because this is just an add-on module to a commercial microscope,” says Mir. “Biologists can use all their old tricks and just add our module on top.”

Because of SLIM’s sensitivity, the researchers could monitor cells’ growth through different phases of the cell cycle. They found that mammalian cells show clear exponential growth only during the G2 phase of the cell cycle, after the DNA replicates and before the cell divides. This information has great implications not only for basic biology, but also for diagnostics, drug development and tissue engineering.

The researchers hope to apply their new knowledge of cell growth to different disease models. For example, they plan to use SLIM to see how growth varies between normal cells and cancer cells, and the effects of treatments on the growth rate.

Electrical and computer engineering professor Gabriel Popescu, a member of the Beckman Institute for Advanced Science and Technology at the U of I and who led the research team, is establishing SLIM as a shared resource on campus, hoping to harness its flexibility for basic and clinical research in a number of areas.

The National Science Foundation and the Grainger Foundation supported this work, which has been published in the in the Proceedings of the National Academy of Sciences.

-----

Follow us on Twitter, 'like' us on Facebook, and join our group on LinkedIn

Follow OptoIQ on your iPhone; download the free app here.

Subscribe now to BioOptics World magazine; it's free!

Sponsored Recommendations

Next generation tunable infrared lasers

Nov. 28, 2023
Discussion of more powerful and stable quantum cascade tunable infrared lasers, applications, and test results.

What AI demands mean for data centers

Nov. 28, 2023
The 2023 Photonics-Enabled Cloud Computing Summit assembled by Optica took an aggressive approach to calling out the limitations of today’s current technologies.

SLP feature for lighting control available on cameras offering

Nov. 28, 2023
A proprietary structured light projector (SLP) feature is now available on the company’s camera series, including the ace 2, boost R, ace U, and ace L.

Chroma Customer Spotlight - Dr. David Warshaw, About his Lab

Nov. 27, 2023
David Warshaw, Professor and Chair of Molecular Physiology and Biophysics at the University of Vermont (UVM), walks us through his lab. Learn about his lab’s work with the protein...

Voice your opinion!

To join the conversation, and become an exclusive member of Laser Focus World, create an account today!