Researchers' smartphone 'microscope' can detect a single virus, nanoparticles

Sep 17, 2013 by Bill Kisliuk

(Phys.org) —Your smartphone now can see what the naked eye cannot: A single virus and bits of material less than one-thousandth of the width of a human hair.

Aydogan Ozcan, a professor of electrical engineering and bioengineering at the UCLA Henry Samueli School of Engineering and Applied Science, and his team have created a portable smartphone attachment that can be used to perform sophisticated field testing to detect without the need for bulky and expensive microscopes and lab equipment. The device weighs less than half a pound.

"This cellphone-based imaging platform could be used for specific and sensitive detection of sub-wavelength objects, including bacteria and viruses and therefore could enable the practice of nanotechnology and biomedical testing in field settings and even in remote and resource-limited environments," Ozcan said. "These results also constitute the first time that single nanoparticles and viruses have been detected using a cellphone-based, field-portable imaging system."

The new research, published on Sept. 9 in the American Chemical Society's journal ACS Nano, comes on the heels of Ozcan's other recent inventions, including a cellphone camera–enabled sensor for allergens in food products and a smart phone attachment that can conduct common kidney tests.

Capturing clear images of objects as tiny as a single virus or a nanoparticle is difficult because the strength and contrast are very low for objects that are smaller than the .

In the ACS Nano paper, Ozcan details a device fabricated by a 3-D printer that contains a , an external lens and a . The diode illuminates fluid or solid samples at a steep angle of roughly 75 degrees. This oblique illumination avoids detection of that would otherwise interfere with the intended fluorescent image.

Using this device, which attaches directly to the camera module on a smartphone, Ozcan's team was able to detect single human cytomegalovirus (HCMV) particles. HCMV is a common virus that can cause birth defects such as deafness and brain damage and can hasten the death of adults who have received organ implants, who are infected with the HIV virus or whose immune systems otherwise have been weakened. A single HCMV particle measures about 150–300 nanometers; a human hair is roughly 100,000 nanometers thick.

In a separate experiment, Ozcan's team also detected —specially marked fluorescent beads made of polystyrene—as small as 90–100 nanometers.

To verify these results, researchers in Ozcan's lab used other imaging devices, including a scanning electron microscope and a photon-counting confocal microscope. These experiments confirmed the findings made using the new cellphone-based imaging device.

Explore further: A nanosized hydrogen generator

More information: pubs.acs.org/doi/pdfplus/10.1021/nn4037706

Related Stories

Cell phone camera photographs microscopic cell samples

Apr 11, 2013

On April 11th JoVE (Journal of Visualized Experiments) will publish a new video article by Dr. Aydogan Ozcan demonstrating how a cell phone camera can capture images from a fluorescent microscope and flow cytometer, whic ...

Recommended for you

Engineers show light can play seesaw at the nanoscale

20 hours ago

University of Minnesota electrical engineering researchers have developed a unique nanoscale device that for the first time demonstrates mechanical transportation of light. The discovery could have major ...

A nanosized hydrogen generator

Sep 20, 2014

(Phys.org) —Researchers at the US Department of Energy's (DOE) Argonne National Laboratory have created a small scale "hydrogen generator" that uses light and a two-dimensional graphene platform to boost ...

For electronics beyond silicon, a new contender emerges

Sep 16, 2014

Silicon has few serious competitors as the material of choice in the electronics industry. Yet transistors, the switchable valves that control the flow of electrons in a circuit, cannot simply keep shrinking ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

John92
not rated yet Sep 17, 2013
nice