The Glassy Carbon Electrode Modified With Sulfide Was Used To Detect Low Concentration Of Berberine And Ascorbic Acid

Nowadays,the pharmaceutical industry is in a period of vigorous development,While satisfying the needs of human medical treatment,it also has a serious impact on the ecological environment.Every year,A lot of organic wastewater which is difficult to be biodegraded will be produced in drug production.which is the root cause of environmental pollution.Therefore,the detection of the concentration of organic drugs in the waste water of the pharmaceutical factory has become a focus of attention.In this paper,two common drugs,berberine and ascorbic acid,produced by Northeast Pharmaceutical Co.,LTD.,were used as samples for analysis and testing,and the work of real-time monitoring of drug content in the wastewater produced by berberine and ascorbic acid was carried out.Electrochemical sensor has become one of the most popular detection methods in recent years due to its advantages of high sensitivity,strong selectivity,simple preparation and real-time detection.The latest research has found that sulfide has the catalytic activity of strong electrocatalytic oxidation of macromolecular organic compounds,and also has excellent electrical conductivity.Go has a high specific surface area,strong electrical conductivity and good biocompatibility,making it an ideal catalyst carrier.The synergistic effect of sulfide and go makes the composite materials widely used in the field of electrocatalysis.Therefore,in this experiment,the application of sulphide modified glassy carbon electrode to the detection of low concentration of berberine and ascorbic acid in wastewater was studied,and the electrocatalytic oxidation mechanism of berberine and ascorbic acid was studied.In this paper,cadmium sulfide（CdS）materials were synthesized by solvent-thermal method.CdS materials with different particle sizes were obtained by changing the growth regulator,characterized by SEM and XRD,etc.,and the morphology and composition of CdS materials were analyzed.It was modified to glassy carbon electrode for detection of low concentration berberine,and the effect of scanning rate and buffer p H value on the performance of the sensor was investigated.The electrochemical oxidation mechanism of berberine was studied.The results show that CdS modified glassy carbon electrode can significantly enhance the oxidation current peak of berberine.The reaction of berberine on the electrode is controlled by the diffusion process.When the applied voltage was 0.5～1.4 V,the potential increment was 0.018 V,and the buffer solution p H was 6,the concentration of berberine in the range of 1～200mg/L presented a good linear relationship with the oxidation current peak.The linear regression equation was Ip=0.37ρ+51.877（R²=0.9943）,and the detection limit was0.15mg/L.MS software was used to analyze the three-dimensional configuration of berberine molecules,electronegativity and electron cloud density between each atom.The infrared spectra of berberine before and after electrolysis were compared.It was concluded that the oxidation of berberine was caused by the methoxy demethylation at position 9 of berberine and the ring-opening and demethylation of methylene.In this experiment,the bimetallic composite NiCo₂S₄/GO was prepared by solvent thermal method.The morphology and composition of NiCo₂S₄/GO material were analyzed by SEM,XRD and other characterization techniques,and modified to glassy carbon electrode for the detection of low concentration ascorbic acid,and the effects of scanning rate and working potential on the performance of the sensor were investigated.The results show that the modified electrode has a good specificity recognition ability of ascorbic acid,by comparison to select the optimal working potential 0.3 V,Abe current time method is used to obtain ascorbic acid concentration in 0.5～110 mg/L within the scope of the standard curve,the linear regression equation for Ir=0.084ρ+1.294（R²=0.9997）,the detection limit of 0.20 mg/L,through MS software analysis of ascorbic acid molecules between three-dimensional configuration and each atom electronegativity,the density of electron cloud.The infrared spectra of ascorbic acid before and after electrolysis were compared.Finally,it is concluded that the oxidation of ascorbic acid is a process in which the carbon-carbon double bond in the molecule breaks the bond and connects to the oxygen atom on the hydroxyl group to form the carbon-oxygen double bond.