The global effort to develop a coronavirus vaccine in 2020 stressed the need for a better way to test biopharma products for endotoxins. The current standard, which relies on an extract derived from horseshoe crab blood, is required by the FDA and ensures that substances like vaccines don’t transmit illness-carrying bacteria. But the process of making the extract is expensive and is damaging to the horseshoe crab population. Four Penn students — Aravind Krishnan C25 W25, Andrew Diep-Tran W25, Udit Garg ENG25, and Aarush Sahni C25 — won the Perlman Grand Prize at this year’s Venture Lab Startup Challenge with ToxiSense, which genetically engineers bioluminescent plants to glow when exposed to endotoxins. Not only is this testing method more cost-effective; it could save the threatened horseshoe crabs from overharvesting.