Krista D. Zanolli, firstname.lastname@example.org
LOS ANGELES – With just a few modifications, a cell phone can become a powerful and affordable medical diagnostic tool that can be used to monitor HIV and malaria in even the most remote regions around the globe.
In the lab of Aydogan Ozcan, assistant professor of electrical engineering at the UCLA School of Engineering and Applied Science and a member of the California NanoSystems Institute, a prototype cell phone that can perform on-the-spot disease detection has been developed. This advancement, a major milestone, could prove particularly beneficial for those seeking medical attention in resource-limited regions such as Africa.
Lucas acquires images by way of a short-wavelength blue light that illuminates the sample, casting a detailed shadow onto the sensor. Images courtesy of Aydogan Ozcan, UCLA.
Using standard CCD light sensors and without using any lens optics, Ozcan can distinguish between normal and infected cells in blood samples. The imaging platform, known as Lucas (lensless ultrawide-field cell monitoring array platform based on shadow imaging), acquires cell images by way of a short-wavelength blue light that illuminates the blood or fluid sample and casts a unique and detailed shadow onto the sensor.
In this lens-free Lucas image, each cell type exhibits a characteristic detailed image, which allows for digital sorting of different cell types within a heterogeneous solution. The data from a cell phone can be sent via USB to a computer for transmission to a hospital.
Once an image of the sample is captured, Lucas’ custom-developed “decision algorithm” can almost instantaneously identify and compare that image to an entire library of diseased cell images. The data can then be sent to a hospital for analysis and diagnosis using the cell phone, or transferred via USB to a computer for transmission to a hospital.
While the Lucas’ advantage lies in its speed and small size, it is certainly no substitute for a microscope, but rather a complement.
“This on-chip imaging platform may have a significant impact, especially for medical diagnostic applications related to global health problems such as HIV or malaria monitoring,” Ozcan said.
Typically, cell counting is done by large machines called flow cytometers, which cost hundreds of thousands of dollars, or by a trained technician, who has the tedious task of manually sifting through samples under a microscope.
“This technology will not only have great impact in health care application, it also has the potential to replace cytometers in research labs at a fraction of the cost,” Ozcan added. “A conventional flow cytometer identifies cells serially, one at a time, whereas tabletop versions of Lucas can identify thousands of cells in a second, all in parallel, with the same accuracy,” he explained.
What’s more, because the sensor does not use a lens, the only size restriction is the size of the chip that the sensor is built on, making it portable and less expensive.
“This is the first demonstration of automated, lens-free counting and characterization of a mixed, or heterogeneous, cell solution on a chip, and it holds significant promise for telemedicine applications,” Ozcan said.
Having successfully installed the Lucas in both cell phones and webcams, Ozcan began working to improve the system so that smaller particles such as E. coli can be detected. The new achievement has been dubbed the holographic Lucas.
Controlling the special properties of the light source enables capture of a two-dimensional holographic shadow image of the microparticles, which contains even more information than the classic shadow image. And according to Ozcan, the new handheld portable holographic Lucas remarkably weighs less than 0.2 pounds.