Preparation And Application Of Molybdenum Disulfide Nanometer Material Modified Electrochemical Sensor

ObjectiveWith the rapid progress of drug analysis technology,electrochemical drug sensors have begun to show the prominence of itself in the field of drug detection.Molybdenum disulfide nanomaterials have excellent physicochemical properties and have become a research hotspot in recent years.Molybdenum disulfide nanosheet materials were prepared by improved mechanical exfoliation method and applied to modify glassy carbon electrode to establish electrochemical drug sensors to achieve rapid simultaneous detection of sulfamethoxazole and the simultaneous detection of adenine(A),guanine(G),thymine(T),cytosine(C)and uracil(U).The methods for detecting sulfamethoxazole and various bases include high performance liquid chromatography,capillary electrophoresis,etc..Most of these method have the limitations of complicated operation methods and high cost.Therefore,it is very important to establish an electrochemical drug sensor with simple preparation structure,convenient use and low cost.In this paper,the specificity and sensitivity of the established electrochemical drug sensors were studied,and the experimental conditions were screened to obtain the best performance of the electrochemical sensor.To provide technical and methodological support for further broadening the application of molybdenum disulfide nanosheets in electrochemical sensors.MethodsBulk molybdenum disulfide was put into m-xylene and grinded continuously until m-xylene was completely volatilized.Ethanol was added to grind continuously until ethanol was completely volatilized.Ethanol was added to grind continuously,and the above process was repeated 30-40 times.Controlling the ultrasonic conditions,the grinding materials were subjected to ultrasonic treatment,and molybdenum disulfide sheet materials with different sizes were screened by step centrifugation.Atomic force microscopy(AFM),scanning electron microscopy(SEM),X-ray diffraction(XRD)characterization techniques were used to observe the morphology and structure of the materials,and determine the size and distribution of the materials.The prepared molybdenum disulfide nanosheet materials were modified on the glassy carbon electrode,and the blank glassy carbon electrode and the molybdenum disulfide modified electrode was pretreated by the i-t curve method.The effects of the modified electrode on sulfamethoxazole,adenine,guanine,thymine,cytosine and uracil were studied by cyclic voltammetry(CV)and differential pulse voltammetry(DPV).Electrochemical activity response properties of seed bases.ResultsThe results of AFM and SEM characterization prove that the molybdenum disulfide nanosheet materials with different thicknesses can be successfully obtained by the combined grinding ultrasonic method and step centrifugation method,and the materials have uniform morphology and size distribution.Determination of sulfamethoxazole,molybdenum disulfide Nanomaterial Modified electrode has better electrochemical activity than blank glassy carbon electrode,and shows a good linear relationship in a certain concentration range.It was preliminarily proved that the prepared molybdenum disulfide nanosheet material had good electrochemical catalyticperformance.The stability experiment shows that the modified electrode has good stability,which provides a feasible method for further development of sulfamethoxazole electrochemical sensor.The electrodes were pretreated and screened to obtain the best pretreatment conditions.The pretreatment process can make the drug aggregate on the electrode surface and increase the drug concentration significantly,thus increasing the peak current of the drug reaction on the electrode surface and improving the sensitivity of the sensor.The use of acetonitrile solution as electrolyte can effectively provide a broader potential window so that five bases can be successfully determined simultaneously.Modified electrode showed more excellent electrochemical activity than glassy carbon electrode for the determination of adenine,guanine,thymine,cytosine and uracil,which could further prove that the prepared molybdenum disulfide nanosheet material had excellent electrochemical catalytic performance.It provides a sensitive electrochemical detection method for simultaneous determination of five bases,such as adenine,guanine,thymine,cytosine and uracil.ConclusionsThe results of AFM and SEM show that the materials with different thickness can be successfully obtained by the combination of ultrasonic grinding and step-by-step centrifugation,and the materials have uniform morphology and size distribution.Compared with the blank glassy carbon electrode,the molybdenum disulfide modified electrode has better electrochemical activity,and shows a good linear relationship within a certain concentration range.The results show that the prepared molybdenum disulfide nanosheets have good electrocatalytic properties.The stability experiment shows that the modified electrode has good stability,which provides a feasible method for further development of sulfamethoxazole electrochemical sensor.Compared with the glass carbon electrode,the modified electrode showed more excellent electrochemical activity in the determination of adenine,guanine,thymine,cytosine and uracil.It can be further proved that the prepared molybdenum disulfide nanosheets has excellent electrochemical catalytic performance.The use of acetonitrile solution as electrolyte can effectively provide a wider potential window,so that five bases can be successfully determined at the same time.The pretreatment process can make the drug aggregate on the electrode surface and increase the concentration of the drug significantly.Therefore it can increase the peak current of the drug reaction on the electrode surface and improve the sensitivity of the sensor.The optimal experimental conditions were obtained by screening the pretreatment conditions,which provided a sensitive electrochemical detection method for the simultaneous determination of adenine,guanine,thymine,cytosine and uracil.