Engineers from the California Institute of Technology (CalTech) have unveiled the ePetri dish: a small, lens-free microscopy imaging platform. The prototype was built using a smartphone, a commercially available cell-phone image sensor and Lego building blocks. The device is described in this week’s Proceedings of the National Academy of Sciences (PNAS).
The culture is placed on an image sensor chip and the phone’s LED screen functions as a scanning light source. The ePetri device is then placed in an incubator, with the image sensor chip connected to a laptop outside the incubator through a cable. The image-sensor takes pictures of the culture, the data is sent to the laptop and so cultures can be monitored as they grow. The technique is apparently particularly useful in the imaging of cells that grow very close to one another.
Instead of using a large, heavy instrument, they now have a lightweight microscope providing high-quality images of cells. The ePetri is able to monitor the entire field, but can still zoom in on areas of interest within the culture. The research team sees many possibilities for their technology, such as drug screening and detection of toxic compounds. It could even provide microscopy-imaging capabilities for other portable diagnostic lab-on-a-chip tools. Right now the team is also working on a more comprehensive system that would include a small incubator, transforming the ePetri into a desktop diagnostic tool.
Here you can see how the ePetri prototype works: