A bioinspired polymeric membrane-enclosed insulin crystal achieves long-term, self-regulated drug release for type 1 diabetes therapy.

Summary: Imagine a "smart wrapper" for insulin inspired by the protective envelope of a cell nucleus. Scientists have created a microscopic polymer skin that forms directly on insulin crystals. This skin acts like an intelligent gatekeeper: when blood sugar or ketone levels are normal, the pores stay tight, keeping the insulin inside. But if sugar or ketones spike—signaling danger—the skin becomes electrically charged, widening the pores to release insulin instantly. In tests with diabetic mice and minipigs, a single injection of these smart crystals maintained healthy blood sugar levels for weeks, effectively functioning like an artificial pancreas without the machinery.