A completely self-contained miniature fluorescence microscope small and robust enough to be carried on the head of a mouse is reported online in Nature Methods. This microscope can be used as a portable field instrument or arranged in arrays of multiple microscopes for parallel imaging of many samples.
Considerable effort has been expended on developing portable low-cost microscopy systems for applications ranging from neuroscience to field diagnostics, but such systems have had considerable limitations. Mark Schnitzer and colleagues describe a widely applicable fluorescence microscope that weighs only 1.9 grams and is built using mass-producible parts that include everything from the light source to the optics and the image detector. Its many potential uses were demonstrated by imaging blood flow and neuronal signaling in a freely behaving mouse, by parallel imaging of zebrafish, and by counting of cultured cells and bacteria as a way to assess future utility in diagnostic applications.
The authors believe the design of the system will permit straightforward low-cost mass production. Although there is still room for improvement, the performance approaches that of standard full-size fluorescence microscopes.