Stabilizing Carbonic Anhydrase at Elevated Temperatures via Amine-Functionalized Boron Nitride Nanosheets

Capturing carbon dioxide (CO₂) remains a critical challenge in mitigating climate change due to its stability and low reactivity. Carbonic anhydrase (CA), a highly efficient enzyme capable of converting CO₂ to bicarbonate at a turnover rate of up to 1 × 10⁶ s^-1, presents a promising solution for carbon capture and storage (CCS). However, its industrial application is limited by poor thermal and chemical stability, especially under harsh conditions such as those found in flue gas streams. This study addresses this limitation by employing interfacial engineering to immobilize CA on amine-functionalized boron nitride nanosheets (BNNS-NH₂), forming robust two-dimensional catalytic adsorbents. Experimental results demonstrated that the CA@BNNS-NH₂ hybrid not only retained structural integrity under denaturing conditions but also exhibited enhanced thermal stability at 80 °C, and it achieved high catalytic activity compared to that of free CA, suggesting improved efficiency through enzyme-nanomaterial synergy. Molecular dynamics simulations supported these findings by revealing that BNNS-NH₂ creates a stabilizing microenvironment for CA via electrostatic interactions, salt bridges, and hydrogen bonding. This study offers a scalable and effective strategy for improving enzyme resilience and activity, opening pathways for more efficient and sustainable CO₂ capture technologies in industrial settings.