Research On Temperature Sensitive Electrochemical Sensor Based On MEO₂MA Polymer

In recent years,the application of electrochemical sensors in the fields of environmental monitoring,biomedicine,biotechnology,food safety,medicine,and clinical diagnosis has continued to increase.With the increasing requirements for sensitivity and selectivity,electrochemical sensors made of a single modified material can no longer meet actual needs.Irritation-responsive polymer is a new type of polymer material that can quickly respond to small external stimuli and then change physical or chemical properties.The application of stimulus-responsive polymers to electrochemical sensors can improve their selectivity and achieve sensor intelligence,while the addition of carbon nanomaterials and quantum dots can greatly improve the stability and sensitivity of electrochemical sensors.In this paper,carbon nanomaterials,quantum dots and temperature-sensitive polymers are mixed to prepare composite materials to modify the electrodes,and a series of electrochemical sensing platforms with temperature stimulus response effects are constructed to achieve intelligent switch detection of different target detection objects.The contents are as follows:?1?Through reversible addition-fragmentation chain transfer?RAFT?polymerization,2-methyl-2-acrylic acid-2-?2-methoxyethoxy?ethyl ester?MEO₂MA?and tert-butyl acrylate?TBA?Is a monomer,azobisisobutyl cyanide?AIBN?is an initiator,and S-n-dodecyl-S'-?2-isobutyrate?trithiocarbonate?DDMAT?is a chain transfer agent,1,4-dioxane was synthesized as a temperature-responsive polymer P?MEO₂MA-co-TBA?as a solvent,which was mixed with carbon nanotubes to prepare a composite material to modify the surface of the glassy carbon electrode.It was found through experiments that the detection limit of P?MEO₂MA-co-TBA?/MWCNTs-COOH composite modified electrode at 50?for detection of acetaminophen?AP?was 0.085?M,and the linear range was 0.3?M?12.7?M and 12.7?M?102.3?M.At the same time,it has good reversibility in the temperature range of 20??50?.?2?Cd S-QDs were synthesized by hydrothermal method,and they were prepared with temperature sensitive polymer P?MEO₂MA-co-MAA?and carboxylated carbon nanotubes?MWCNTs-COOH?.The composite materials were modified and constructed on glassy carbon electrodes An intelligent"zipper switch"electrochemical sensor is used to detect catechol?CC?.Experiments show that the detection limit of P?MEO₂MA-co-MAA?/Cd S-QDs/MWCNTs-COOH modified electrode for CC detection is 0.13?M and the linear range is 0.2?51.1?M,and it also has good reversibility and stability.?3?First,temperature-sensitive polymer P?MEO₂MA-NMA?was synthesized,and then it was combined with Zn S-QDs and MWCNTs-COOH to prepare a composite membrane with temperature-sensitive effect.Using the composite membrane modified glassy carbon electrode,an intelligent"zipper switch"electrochemical sensor for detecting?Quinol?HQ was constructed.At low temperatures,the P?MEO₂MA-NMA?structure is in a diffuse state and the interface resistance is high,so the electron transfer rate is slow,and the electrochemical behavior of HQ on the composite electrode is"off";at high temperatures,the P?MEO₂MA-NMA?structure shrinks and the interface With low resistance and fast electron transfer rate,the electrochemical behavior of HQ on the composite electrode"turns on".Moreover,repeated temperature rise and fall,the modified electrode has good reversibility.The experimental results show that the detection limit of hydroquinone on the modified electrode is 0.0129?M,and the linear range is 0.1?204.7?M.