The small intestine is a hotbed of microbial activity and a target of probiotic treatments for diarrhea, inflammatory bowel disease and irritable bowel syndrome, among other conditions. To make it to the intestine, though, probiotics must first pass through the stomach, a hostile acidic environment that can kill these beneficial bacteria. Now, scientists report in ACS Sustainable Chemistry & Engineering the development of a protective gel sphere that may offer probiotics a safer route.