By Janet Fang
Posting in Cancer
Possibly the world's fastest, a microscopic camera that captures six million frames per second can help detect cancer early, using a simple blood test.
Scientists have developed the world’s fastest camera, and at six million frames per second, it can detect cancer cells from a simple blood test.
Cells that break away from a cancerous tumor and circulate in the bloodstream help spread cancer to other parts of the body. Finding them is the key to early cancer detection… but in every milliliter of blood, there are 5 billion red blood cells, 10 million white blood cells, and only 10 of these circulating tumor cells.
So how do you quickly examine billions of rapidly moving blood cells in a sample at a resolution high enough to identify the cancerous intruders? Scientific American reports.
A team led by Keisuke Goda at the University of California, Los Angeles, is developing a system that combines a microscope with a device for counting and studying cells, along with a high-speed image processor that can take sharp images of fast-moving cells.
- Their ultrafast microscopic camera captures images at about six million frames per second.
- This ‘serial time-encoded amplified microscopy’ (STEAM) camera creates each image using a very short laser pulse -- a flash of light a billionth of a second long.
- The shutter speed is 27 picoseconds, about a million times faster than a current digital camera. (A picosecond it one trillionth of a second.)
- The STEAM flow analyzer is an automated microscope 100 times faster than the automated microscopes hospitals use for disease identification.
- The camera converts each laser pulse into a data stream. And from this, a high-speed image can be assembled.
"We look at the cell's shape, size and texture as well as its surface biochemistry," Goda explains. "Cancer cells tend to be larger and more ill-defined than white or red blood cells.
Then they tried this out with breast cancer cells in a blood sample, and they got a record low false-positive rate of one cell in a million, according to a UCLA news release.
They’re now testing their noninvasive technique with breast, lung, stomach, prostate, and intestinal cancer patients' blood samples, and they hope to widen that to include the fast-spreading ovarian and pancreatic cancers.
The diagnostic tool currently on the market for identifying and counting circulating tumor cells is the CellSearch system made by Johnson & Johnson's Veridex unit. But that system isn’t optimized for early detection, rather, it’s used to check the progress of treatment.
The work was published in the Proceedings of the National Academy of Sciences last month.
[Via Scientific American]
Image: breast CTC / Scripps Research Institute
Aug 16, 2012