Research And Application Of Portable Electrochemical Sensors Based On Laser Etching Technology

As the standard of living continues to improve,people are more concerned about their health.The use of preservatives,antimicrobial agents,and antioxidants is becoming more common in the medical field and in food products.Sulfites and gallic acid are two common drugs that are commonly used as preservatives.However,the misuse of these drugs can lead to nutrient destruction and human damage,so a rapid and accurate test is needed to ensure that these drugs are being used appropriately.Electrochemical detection can be used for drug-related detection,where the electrode material determines its detection performance.In this paper,we propose a laser-induced graphene-based technique using a mixture of copper acetate and graphene oxide paired with a one-step method to prepare multi-dislocated copper oxide nanoparticles（Cu O）and attach them to the graphene surface,and using various material characterization methods,we verified that the prepared material is a nanoscale structure of multi-dislocated particles attached to graphene leaves with the particle composition of copper oxide.In this paper,traditional laboratory electrodes were discarded and a homemade flexible screen-printed electrode was chosen,which can be made in bulk and paired with a portable electrochemical workstation and a snap-in interface made specifically for it to enable portable detection.The nanometric properties of the multi-dotted Cu O nanoparticles attached to the graphene blade and the multi-level structure of the graphene blade,coupled with the small size response,further enhance the performance of the sensor,leading to the construction of the Cu O/r GO/SPE electrochemical sensor electrode.In this paper,the Cu O/r GO/SPE electrode is applied to the testing and analysis of small concentrations of SO₃^2-and gallic acid.The prepared graphene blade with petal shape and large specific surface area as well as the multi-sited Cu O nanoparticles with a particle size of about 30 nm attached to it act as highly dispersed multi-sited active centers,which help to fully contact with the analytes to be detected.The electrode was operated at 0.3V for the detection of low concentration of SO₃^2-.The electrode current response was linear with the concentration of SO₃^2-in the range of 1-300 u M,the electrode sensitivity was 122.3μAcm^-2m M^-1,and the detection limit was 0.2425 u M.The electrode was operated at 0.4 V for the detection of low concentration of gallic acid,and the electrode current response was linear with the concentration of gallic acid in the range of 10-100 u M.The linear response range was10-100μM,the sensitivity was 346.5μAcm^-2m M^-1,and the detection limit was0.085μM.The results were more satisfactory for the detection of SO₃^2-and gallic acid using this electrode.the Cu O/r GO/SPE modified electrode showed remarkable selectivity,stability and reliability.The use of this multisite copper oxide nanocomposite graphene electrochemical sensor combined with a portable electrochemical workstation with a dedicated snap-in interface constitutes a simple and rapid method for the determination of SO₃^2-and gallic acid in the pharmaceutical and food industries.