Tailoring the Properties of Self-Assembled Carbonic Anhydrase Supraparticles for CO<sub>2</sub> Capture
Guanzhang Liu, Hang Yuan, Xiaobo Li, Ke Li, Lei Mao, Guangya Zhang
Abstract
Carbon dioxide capture, conversion, and utilization with carbonic anhydrase (CA) as a green and sustainable method still faces the challenges of complex and costly purification, relatively low yield, and poor catalytic performances and reusability. Herein, we proposed an all-in-one strategy to solve these problems by self-assembling nanosized CA oligomeric particles (nCAOPs) into micrometer-sized CA supraparticles (mCASPs) with well-designed tags. The preparation of the purified mCASPs was simple and effective by an easy scalable low-speed centrifugation method with 78% activity recovery. The obtained mCASPs with a yield of 870 mg/L was the reported highest yield of CAs. Interestingly, mCASPs could serve as carrier-free immobilized CAs and retain over 90% original activity after 15 reuse cycles. More encouragingly, mCASPs could redissolve and form nCAOPs, which had excellent catalytic performances. The hydrated activity of nCAOPs was 1.05 times that of free CAs. Also, the kcat/Km value was 1.74 times that of free CAs, and the half-life at 40 °C was 3.83 times that of free CAs. Due to the simplicity of purification and immobilization, high yield, and excellent enzymatic properties, mCASPs and nCAOPs are considered novel bioactive materials, which offer the feasibility of CAs for sustainable CO2 capture to achieve the target of carbon neutrality.