Development And Enrichment Mechanism Of Uranyl Adsorbents Based On DNA

Extracting uranium from seawater is a potential key strategy to ensure the sustainable development of nuclear energy.However,the existing adsorbents for uranium extraction are seriously disturbed by the coexisting metal ions in seawater,and the efficiency of uranium extraction in natural seawater is not high.DNAzyme is a kind of functional nucleic acid molecule with catalytic effect obtained by screening in vitro.Based on its high selective performance,a variety of DNAzymes with high selective detection performance for specific metal ions have been developed in recent years,including those with specific detection performance for uranyl ions.However,there is no DNA-based adsorbent for uranium extraction from seawater,and the recognition mechanism of DNA enzymes for specific metal ions(including uranyl)is still unclear.This study aims to develop a new adsorbent for extracting uranium from seawater.Inspired by the high selectivity and specificity of DNA enzyme for specific metal ions,based on the specific DNAzyme-39 E binding with uranyl,template sequences and primers were designed,and DNA-UEH hydrogels were amplified by isothermal rolling loop amplification under the action of biological enzymes.The hydrogel has excellent uranium extraction performance in natural seawater,has high selectivity for uranyl,and has the ability to extract uranium in natural seawater.The selectivity of DNA-UEH hydrogel to uranium is 18.95 times that of 6.06 mg/g.XPS and EXAFS analysis explored the mechanism of the enrichment reaction of uranyl ions,and revealed that the high selectivity of DNA-UEH hydrogel to uranyl was attributed to the formation of a specific nano pocket structure of DNA and uranium.At the same time,DNA-UEH hydrogel also has excellent mechanical properties and recycling reusability.which is expected to achieve its true application in the extraction of uranium from seawater.This study not only provides a new adsorbent for extracting uranium from seawater,but also broadens the application scope of DNA,which is conducive to the extraction and recovery of more high priced soluble minerals from seawater.