Spatiotemporal modulation of microalgae to boost biofuel generation from CO2 by the stick-to-culture strategy

The accelerating global energy demand, coupled with diminishing fossil fuel reserves and growing carbon emissions, underscores the urgent need for sustainable energy solutions. Autotrophic microalgae are promising cell factories for converting CO2 into renewable biofuels. However, conventional microalgal biofuels typically depend on energy-intensive or nutrient-deficient regimes that suppress microalgal proliferation, resulting in a critical trade-off between biomass growth and lipid biosynthesis. Here, we report a separable living interface with microalgae (SLIM) platform that employs extracellular-matrix-mimicking hydrogel scaffolds to spatially organize microalgae and dynamically reconfigure their microenvironment, enabling spatiotemporal switching between biomass accumulation or lipid induction. The SLIM platform supports high-density growth of microalgae while facilitating precision substrate-driven metabolic regulation, enabling low-carbon operation and improved lipid production (8.89 g L−1). This work establishes an engineered living material that overcomes essential bottlenecks in microalgal biofuel production and offers a generalizable blueprint for biohybrid systems in advanced biomanufacturing. Balancing biomass growth and lipid accumulation remains a challenge in microalgal biofuel production. Here the authors report extracellular matrix-mimicking hydrogel scaffolds that dynamically reconfigure the microenvironment of spatially organized microalgae, allowing controlled switching between the two states.