Their so-called ePetri platform could potentially make cumbersome microscopes a thing of the past. The group also says their prototype reduces human labor time and improves the way in which culture growth can be recorded.
"Our ePetri dish is a compact, small, lens-free microscopy imaging platform. We can directly track the cell culture or bacteria culture within the incubator," explained Guoan Zheng in a Caltech news release. Zheng is lead author of the study and a graduate student in electrical engineering at Caltech.
Cultures are places inside the image-sensor chip while the smart phone's LED screen serves as a scanning light source. After the device is placed in an incubator, the image sensor snaps a photo of the culture. That data is sent to a laptop via a wire running from the incubator to the computer. This allows researchers to capture images of cells as they grow in real time.
The ePetri device is particularly good at capturing images of cells that grow very close together, known as confluent cells.
"Until now, imaging of confluent cell cultures has been a highly labor-intensive process in which the traditional microscope has to serve as an expensive and suboptimal workhorse," Changhuei Yang, senior author of the study and professor of electrical engineering and bioengineering at Caltech, said in a press release. "What this technology allows us to do is create a system in which you can do wide field-of-view microscopy imaging of confluent cell samples. It capitalizes on the use of readily available image-sensor technology, which is found in all cell-phone cameras."