Now in our 13th year of bringing you beautiful imagery from biomedical science every day

Search the archive of over 4000 images

Flashy Techniques
13 April 2012

Flashy Techniques

Scientists try to measure the rapid and tiny electrical pulses that pass along nerve cells with microscopic electrodes. It is hard enough to probe just one cell, let alone a whole network, but now there is a way to ‘see’ pulses move from cell to cell. These images show human cells genetically-engineered to make a light-sensitive protein called rhodopsin. The protein is here detected with fluorescence under laser light (left). Located within the cell membrane, the brightness readings are a measure of the voltage across the membrane. As the voltage increases rhodopsin ‘glows’ more brightly. When a nerve pulse passes by, the protein effectively flashes on and off again. A computer program analyses the flashes (right; red is high voltage, blue is low) allowing scientists to trace impulses passing between cells. Understanding how these biological networks operate is fundamental to developing successful strategies for therapeutic intervention.

Written by Edwin Colyer

Search The Archive

Submit An Image

Follow on Tumblr

Follow on Instagram

What is BPoD?

BPoD stands for Biomedical Picture of the Day. Managed by the MRC Laboratory of Medical Sciences until Jul 2023, it is now run independently by a dedicated team of scientists and writers. The website aims to engage everyone, young and old, in the wonders of biology, and its influence on medicine. The ever-growing archive of more than 4000 research images documents over a decade of progress. Explore the collection and see what you discover. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.

Read More

BPoD is also available in Catalan at with translations by the University of Valencia.