Alex Hogan/STAT The humble pipette tip is tiny, cheap, and utterly essential to science. It powers research into new medicines, Covid-19 diagnostics, and every blood test ever run. It is also, ordinarily, abundant — a typical bench scientist might grab dozens every day. But now, a series of ill-timed breaks along the pipette tip supply chain — spurred by blackouts, fires, and pandemic-related demand — have created a global shortage that is threatening nearly every corner of the scientific world. advertisement The pipette tip shortage is already endangering programs across the country that screen newborn babies for potentially deadly conditions, like the inability to digest sugars in breast milk. It is threatening universities’ experiments on stem cell genetics. And it is forcing biotech companies working to develop new drugs to consider prioritizing certain experiments over others.