Liu Qian, Bai Xinwei, Pham Huy, Hu Jianli, Dinu Cerasela Zoica
Department of Chemical and Biomedical Engineering, West Virginia University, Morgantown, WV 26506, USA.
Nanomaterials (Basel). 2021 Apr 15;11(4):1008. doi: 10.3390/nano11041008.
Carbonic anhydrases are enzymes capable of transforming carbon dioxide into bicarbonate to maintain functionality of biological systems. Synthetic isolation and implementation of carbonic anhydrases into membrane have recently raised hopes for emerging and efficient strategies that could reduce greenhouse emission and the footprint of anthropogenic activities. However, implementation of such enzymes is currently challenged by the resulting membrane's wetting capability, overall membrane performance for gas sensing, adsorption and transformation, and by the low solubility of carbon dioxide in water, the required medium for enzyme functionality. We developed the next generation of enzyme-based interfaces capable to efficiently adsorb and reduce carbon dioxide at room temperature. For this, we integrated carbonic anhydrase with a hydrophilic, user-synthesized metal-organic framework; we showed how the framework's porosity and controlled morphology contribute to viable enzyme binding to create functional surfaces for the adsorption and reduction of carbon dioxide. Our analysis based on electron and atomic microscopy, infrared spectroscopy, and colorimetric assays demonstrated the functionality of such interfaces, while Brunauer-Emmett-Teller analysis and gas chromatography analysis allowed additional evaluation of the efficiency of carbon dioxide adsorption and reduction. Our study is expected to impact the design and development of active interfaces based on enzymes to be used as green approaches for carbon dioxide transformation and mitigation of global anthropogenic activities.
碳酸酐酶是一种能够将二氧化碳转化为碳酸氢盐以维持生物系统功能的酶。最近，将碳酸酐酶进行合成分离并应用于膜中，为减少温室气体排放和人为活动足迹的新型高效策略带来了希望。然而，目前这种酶的应用面临诸多挑战，包括所得膜的润湿性、膜在气体传感、吸附和转化方面的整体性能，以及二氧化碳在水（酶发挥功能所需的介质）中的低溶解度。我们开发了新一代基于酶的界面，能够在室温下高效吸附和还原二氧化碳。为此，我们将碳酸酐酶与一种亲水性的、用户合成的金属有机框架相结合；我们展示了该框架的孔隙率和可控形态如何有助于实现可行的酶结合，从而为二氧化碳的吸附和还原创造功能性表面。我们基于电子显微镜、原子显微镜、红外光谱和比色分析的研究证实了此类界面的功能，而布鲁诺尔-埃米特-泰勒分析和气相色谱分析则进一步评估了二氧化碳吸附和还原的效率。我们的研究有望影响基于酶的活性界面的设计与开发，这些界面将作为二氧化碳转化和缓解全球人为活动影响的绿色方法。
