Research On Solution-Gated Graphene Transistor Sensor Modified By Nanozyme/Porous Carbon Composite For Detection Of Lactate In Metabolites

Effective detection of biomarkers for tumor cells has been the focus of attention.In this work,we have successfully fabricated a highly sensitive sensor based on solution-gated graphene transistors?SGGT?for detecting lactic acid content accumulated in tumor cells through their glycolysis metabolism.The sensing mechanism of the lactic acid sensor is attributed to electrochemical catalysis of H₂O₂produced by the oxidation of lactic acid by lactate oxidase near the gate electrode.The key component of the sensor is the functionalization of porous carbon loaded with ceria nanoparticles derived from a novel one step in situ pyrolysis of pretreated Jerusalem artichoke stalk,which significantly improved the sensor sensitivity.The optimized lactic acid sensor has successfully applied to the detection of lactic acid in practical cell culture samples with high credibility.The SGGT-based lactic acid biosensor shows great potential for the application in tumor microenvironment due to its superior biocompatibility and accuracy.This article focuses on two parts to explore the lactic acid biosensor:1. One-step in-situ synthesis of gate electrode modification materials for electrolyte gate-controlled graphene field-effect transistor sensors and bio-porous carbon composite materials of Jerusalem artichoke straw core loaded with cerium oxide nanoparticles.The feasibility of the modification of the nanocomposite was explored in detail mainly from the design of the synthesis method,the preparation of the composite material,the characterization of the material's biocompatibility and the electrochemical performance of the material.2. Real-time detection of lactic acid content in tumor cell metabolites based on electrolyte gated graphene field effect transistors.Taking the metabolite of tumor cells as the actual sample,combined with the efficient and specific identification of lactate oxidase to recognize lactic acid molecules,catalyze the production of trace amounts of H₂O₂ on the surface of the SGGT gate through the signal amplification effect of the transistor,which can detect the metabolite of tumor cells Changes in real time.The sensor has extremely high sensitivity to lactic acid,the detection limit is as low as 300n M,and the linear detection range is 30?M?300?M.It has been successfully applied to the detection of lactic acid in actual cell culture samples with high confidence.The sensor has good selectivity for certain interfering components in cell metabolites?such as glucose,amino acids and cations?,and the sensor has excellent electrode stability.