After talking the world of communication by storm, cell phones are now set to revolutionise the field of medicine as well.
Scientists at the University of California, Los Angeles (UCLA) have created a cell phone that can monitor the condition of HIV and malaria patients and test water quality at disaster sites and undeveloped areas.
UCLA electrical engineering professor Aydogan Ozcan has constructed the new innovative imaging technology, which has been miniaturized by researchers in his lab to the point that it can fit in standard cell phones.
The imaging platform, known as LUCAS (Lensless Ultra-wide-field Cell monitoring Array platform based on Shadow imaging), has now been successfully installed in both a cell phone and a webcam. Both devices acquire an image in the same way as using a short wavelength blue light to illuminate a blood, saliva or other fluid sample.
LUCAS captures an image of the microparticles in the solution using a sensor array.
As red blood cells and other microparticles have a distinct diffraction pattern, or shadow image, it becomes easier to identify and count them almost instantaneously by LUCAS using a custom-developed "decision algorithm" that compares the captured shadow images to a library of training images.
Data collected by LUCAS 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.
LUCAS is not a substitute for a microscope but rather a complement. Unlike microscopes, which produces detailed images, images produced by LUCAS are grainy and pixelated.
The LUCAS platform's advantage lies in its ability to nearly instantaneously identify and count microparticles, something that is time consuming and difficult to do with a microscope in resource-limited settings. Also, because LUCAS does not use a lens, the only constraint on size is the size of the chip it is built on.
"This technology will not only have great impact in health care applications, it also has the potential to replace cytometers in research labs at a fraction of the cost. 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," said Ozcan.
In the current study, Ozcan described an improvement in the LUCAS system, which he calls holographic LUCAS. This improvement allows for identification of smaller particles such as E. coli that were not previously possible.
It is possible to capture a two-dimensional holographic shadow image of the microparticles by controlling the spatial properties of the light source, and the resulting image contains much more information than the classic shadow image.
Now that Ozcan has successfully created prototypes with a cell phone and webcam, his next step is to build from scratch a handheld device incorporating the LUCAS imaging system.
The device could help people in remote areas of the world to monitor the spread of disease, allowing doctors to focus limited resources in the areas of greatest need.
The system also can be used to monitor water quality by detecting hazardous microparticles. In addition to undeveloped areas, LUCAS would be useful for water testing in the event of a disaster which compromises water quality.
The study has been published in the online edition of the journal Lab on a Chip.