Engineered photosynthetic algae could be used within sunlight-powered sustainable chemical biofactories using a new circular production process developed at KAUST. The scalable process uses bespoke functionalized microparticles—rather than flammable organic solvents—for the critical step of harvesting the valuable chemicals that the algae produce. The microparticles are robust, reusable, and can be tailored to capture a range of chemical products.