Detecting Chloramphenicol In Milk With Electrochemical Sensor Composing Novel Carbon Nitrogen Nanomaterials And Fe-MOFs

Chloramphenicol is a broad-spectrum phenolic antibiotic,which is widely used to treat some animal diseases,but it has adverse reactions such as bone marrow toxicity to animals.Therefore,this study used the antibiotic-chloramphenicol residue in milk as a model,and was committed to developing a simple,convenient,cheap and easy-to-obtain,high specificity,high sensitivity,low detection limit,and it can be used for chloramphenicol in milk on-site.A novel Fe-MOFs composite nano-carbon-nitrogen material electrochemical sensor for residue detection.In this study,Fe-MOFs@N-GQDs/GCE and Fe-MOFs@MWCNTs/GCE sensor were constructed based on Fe-MOFs composite two new carbon and nitrogen materials.A series of physical characterization,electrochemical characterization and optimization of experimental parameters were carried out on these two sensors.Finally,the selectivity,stability and reproducibility of the two sensors were studied,the detection limit and linear equation were calculated,and they were applied to the detection of chloramphenicol in milk samples.The main research contents were as follows:(1)Sensor preparation:Fe-MOFs and N-GQDs were prepared by solvothermal synthesis,and MWCNTs were purified at the same time,and Fe-MOFs@N-GQDs and Fe-MOFs@MWCNTs were prepared by hydrothermal synthesis.At the same time,the prepared Fe-MOFs,N-GQDs,MWCNTs,Fe-MOFs@N-GQDs,Fe-MOFs@MWCNTs were characterized by SEM,FT-IR,and XRD.The results showed that:Fe-MOFs@N-GQDs and Fe-MOFs@MWCNTs were successfully prepared.(2)Sensor characterization and parameter optimization:Under cyclic voltammetry,the current difference?i between the peak-to-peak current corresponding to the specific reduction of chloramphenicol and the baseline was used as the judgment index to optimize the preparation parameters of the two sensors.Fe-MOFs@N-GQDs/GCE sensor optimization experiment results showed that:0.1mol/L sodium chloride solution was the supporting electrolyte,the scan rate of cyclic voltammetry was 100 m V/s,and Fe-MOFs and N-GQDs were dripped The volume ratio was 1:1,the modification amount of Fe-MOFs@N-GQDs dispersion was 5?L,and the p H of the base solution was 7,the sensor's response?i value was the largest.On the other hand,the Fe-MOFs@MWCNTs/GCE sensor optimization experiment results showed that:0.1 mol/L sodium chloride solution was the supporting electrolyte,the scan rate of cyclic voltammetry was 75 m V/s,and Fe-MOFs and MWCNTs were dripped.When the volume ratio was 1:2,the modification amount of Fe-MOFs@MWCNTs dispersion was 6?L,and the p H of the base solution was 7,the sensor's response?i value was the largest.At the same time,the prepared Fe-MOFs@N-GQDs/GCE and Fe-MOFs@MWCNTs/GCE were compared with GCE,Fe-MOFs/GCE,and N-GQDs/GCE,respectively.The electrocatalytic performance of the two sensors was better.The two sensors were characterized by DPV,CV,and EIS in 0.01 mol/L[Fe(CN)6]^3-/4-solution,confirming that the two composite sensors compensate for the conductivity of Fe-MOFs and N-GQDs to a certain extent.The defect of poor performance and the defect of poor dispersion of MWCNTs were improved.(3)The performance and application of the sensor:The Fe-MOFs@N-GQDs/GCE and Fe-MOFs@MWCNTs/GCE sensor were prepared for the determination of selectivity,stability,reproducibility and detection limit,and applied to milk The detection of chloramphenicol.The results showed that the two sensors had good selectivity,stability,reproducibility,and low detection limit.The recovery rate of the detection of chloramphenicol in milk was within the acceptable range,indicating that both sensors have Good applicability.