Chemical Probe Confirms Real-Time that Body Makes Its Own Rotten Egg Gas (1 of 2) (image) Southern Methodist University Share Print E-Mail Caption This is a still image of live human cells shows them generating hydrogen sulfide, H2S, after being treated with a protein that stimulates blood vessel formation. Researchers developed a new fluorescent chemical probe that makes it possible for scientists to observe cells as they generate H2S. Credit SMU Usage Restrictions Please Credit Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.