Preparation And Electrocatalytic Activities For Tetracycline Antibiotics Of Nano Hierarchically Porous Pd-HSiO_1.5/Ni-Co Composite Electrodes

The discovery and use of antibiotics play an important role in improving the level of human health.Antibiotics have been widely used to treat people and animal diseases and promote animal growth.However,the misuse of these medicines may have some adverse affects,such as allergic reactions and antibiotic resistance.Therefore,sensitive and selective methods for their determination in biological fluids are highly advisable.A series of analytical methods have been reported for the determination of antibiotics.Among these methods,electrochemical method has been widely accepted due to the advantages of considerable simplicity,quick response and low cost.Ni-Co alloy has higher electrocatalytic activity towards many organic compounds,such as alcohols,phenols,aldehydes,hydroxyl and other organic compounds.However,most researches are based on the catalytic oxidation of primary alcohols,there are few studies on polyhydroxy antibiotics because the electrochemical detection methods can not meet the needs of high sensitivity and rapid detection.It is beneficial to improve the electrocatalytic activity and sensitivity of the Ni-Co alloy by loading the nano material onto the electrode surface.This paper is committed to the preparation of nanoporous composite electrode and its research on the detection of tetracycline antibiotics,the following research work was carried out:?1?Synthesis of Ni-Co alloy electrode and performance optimization for oxytetracycline detectionThe single pulse electrodeposition experiment of Ni-Co alloy electrode was optimized by single factor orthogonal test method in the citric acid system.And the effects of the bath composition and process conditions?the concentration of CoSO4·7H2O in the plating solution,the average current density of the cathode,the duty cycle,the bath temperature and so on?on the composition and surface morphology of Ni-Co alloy electrode were studied,the optimum bath composition and technological parameters of electrodeposited Ni-Co alloy electrode were obtained eventually.In addition,the effects of different deposition time and components of Ni-Co alloy electrode on the electrocatalytic activity were investigated.Results showed that the Ni-Co alloy electrode had the optimal electrocatalytic activity for oxytetracycline when the concentration of CoSO4.7H2 O was 3 g·L-1,the average cathode current density was 2.5 A·dm-2,the single pulse duty ratio was 10 %,the deposition time was 25 min and the the mass ratio of Ni/Co was 57:43.?2?Preparation of hierarchical nanoporous composite electrode and its performance optimization for oxytetracycline detectionThe hierarchical nanoporous silicon hydride nanoparticles?the size was about 70 nm?were successfully synthesized by dissolving template method using the nonionic surfactant P123 as mesoporous template agent,cationic fluorocarbon surfactant FC-04 as inhibitor and triethoxysilane?TES?as silicon source.The palladium particles were loaded on the hierarchically nanoporous silicon hydrogen nanoparticles using the reduction of silicon hydrogen bond.Finally,the hierarchical nanoporous Pd-HSiO_1.5/Ni-Co composite electrode was prepared by nanocomposite electrodeposition using the nanoporous Pd-HSiO_1.5 particles as the composite particles.Results showed that the Pd-HSiO_1.5/Ni-Co composite electrode had the optimal electrocatalytic activity when the concentration of Pd-HSi O1.5 particles was 2 g/L.?3?Study on antibiotics detection and detection error of the hierarchical nanoporous composite electrodeThe hierarchical nanoporous Pd-HSiO_1.5/Ni-Co composite electrode was applied to the detection of tetracycline antibiotics.Results showed that the hierarchical nanoporous Pd-HSiO_1.5/Ni-Co composite electrode could be used to detect doxycycline,oxytetracycline and tetracycline effectively,and the linear equation was Ip?mA?=9.14+10.15C?mM?,Ip?mA?=10.23+8.87C?mM?and Ip?mA?=10.22+9.13C?mM?respectively.In addition,the repeatability,stability and anti-interference of the composite electrode were studied.Results showed that the hierarchical nanoporous Pd-HSiO_1.5/Ni-Co composite electrode had good stability and repeatability,and there was less interference of other polyhydroxy alcohols and aldehyde antibiotics in the solution.