Research On Application Of Enzyme-Like Activity Of Quaternary Metal Sulfide Materials In Biochemical Analysis

Nanozymes can behave catalytic activity similar to natural enzymes,and show advantages in simplifying procedure of preparation,reducing cost,keeping stable activity and so on,which enable nanozymes to overcome the limitations of natural enzymes in practical applications.The current research on nanozymes is insufficient in theory,the connection between structure and function is yet to be clarified,and the catalytic mechanism still needs to be further studied.The practical application of nanozymes is also limited by catalytic efficiency,selectivity and biocompatibility.The development of novel nanozymes and the enhancement in enzyme mimicking properties can make contribution in improving theoretical research and expanding application fileds,and is still the focus of nanozyme research.Quaternary metal sulfides are metal sulfides containing three metal elements.The diverse compositions and structures enable their excellent electrochemical,optical and catalytic properties to be adjusted to meet the needs of practical applications,and thus have received extensive attention from researchers.Quaternary metal sulfides show great potential of being applied to photocatalysis,electrocatalysis,nonlinear optics and so on,but the research and application in their properties of mimicking enzymes is very rare.According to the relationship between the catalytic mechanism of nanozymes and the outstanding properties of quaternary metal sulfides,this paper designed and synthesized quaternary metal sulfides with the potential of exhibiting excellent enzyme-mimicking activities,and then investigated their properties of simulating enzymes and the catalytic mechanism,finally established colorimetric sensing platform and their explored the feasibility of practical application in analysis and detection.（1）A novel iron cobalt molybdenum quaternary metal sulfide denoted by Fe_0.48Co Mo S_3.75was synthesized through one-step hydrothermal method before investigating its peroxidase-like activity and catalytic mechanism.Based on peroxidase-like activity of Fe_0.48Co Mo S_3.75,a colorimetric detection method for H₂O₂was established,and the antioxidant behavior of ascorbic acid was studied and then a turn-off colorimetric sensing platform was established to detect ascorbic acid.As-established colorimetric detection method for ascorbic acid showed a good selectivity with a linear range as wide as 6.13-140μM and a LOD of 2.22μM,which was successfully applied to detecting ascorbic acid in vitamin C tablets and juice samples.（2）A copper cobalt nickle quaternary metal sulfide denoted by Cu Co_1.25Ni_0.75S₄was synthesized through one-step hydrothermal method,and its peroxidase-like activity and catalytic mechanism were studied.Based on peroxidase-like activity of Cu Co_1.25Ni_0.75S₄,the antioxidant behavior of resveratrol and ascorbic acid was studied and compared,and then a turn-off colorimetric sensing platform was established for resveratrol over a relatively wide linear range of 3.40-60μM with a LOD as low as 0.34μM,which showed good selectivity for resveratrol and was successfully applied to detect resveratrol in red wine samples by standard addition.