Ti₃C₂T_x-based Flexible Wearable Electrochemical Sensor Construction And Sweat Detection Application

As people’s living standards improve,more and more people start to care about their health conditions.We have been working on easy and accurate ways to monitor individuals’health.Electrochemical sensors have excellent detection performance,low cost and other advantages,which enable them to achieve highly sensitive detection of various targets.Therefore,they are widely used in the analysis of different substances.Especially in recent years,by integrating electrochemical sensors with various devices,a series of flexible wearable sensors have been developed to realize real-time monitoring of human health status.In terms of sensor target selection,human sweat contains many physiological indicators related to human health（such as electrolytes,inorganic ions,metabolites and biomolecules,etc.）and has the advantage of easy collection and sampling.Flexible wearable sensors for sweat analysis and detection can realize non-invasive monitoring of biomarkers in sweat and real-time and continuous monitoring of personal health status.This kind of flexible wearable sweat sensor has great potential and wide application prospects in health management and disease diagnosis,and has become one of the research hotspots of chemical sensors in recent years.Based on this,this paper focuses on the new two-dimensional Ti₃C₂T_x MXene material,and constructs flexible wearable electrochemical sweat sensors by modifying and doping the material surface and using screen printing technology.The sensors can realize real-time detection of p H,potassium ions,sodium ions and uric acid in sweat.The main research contents are as follows:1.In this paper,we modified the surface of Ti₃C₂T_x MXene with fluoroalkyl silane for the first time,and changed its hydrophilicity to superhydrophobicity（F-Ti₃C₂T_x）,thus obtaining good stability and hydrophobicity.Then,we ultrasonically inserted polyaniline（PANI）into the interlayer of F-Ti₃C₂T_x to obtain p H-sensitive composite nanomaterials.The material has excellent ion selectivity,stability,anti-interference and anti-water properties.Based on PET and using screen printing technology,we prepared a flexible wearable p H sensor,and successfully realized real-time p H detection in human sweat of volunteers.The measured data were compared with the p H meter,which showed good agreement.2.We used F-Ti₃C₂T_x material as the electrode solid layer material,taking advantage of its hydrophobicity and stability,and combined it with potassium ion and sodium ion selective membrane material.We used screen printing technology to construct a flexible wearable dual-channel electrochemical ion sensor,to realize real-time detection of potassium ion and sodium ion in human sweat.The flexible ion-selective electrode has good flexibility,high ion selectivity and stability,and good anti-interference and repeatability.After detecting and analyzing human sweat of volunteers,the detection results were consistent with those of the electrochemical workstation,indicating that the wearable dual-channel electrochemical sensor prepared in this paper has good real-time monitoring performance of ion concentration changes,and has great application potential in human health management.3.We modified the surface of Ti₃C₂T_x MXene with 1,3,6,8-Pyrene tetracylate（Py TS）（Py TS@Ti₃C₂T_x）to obtain a sensor material sensitive to uric acid and to replace uricase for the detection of uric acid concentration in sweat.We constructed a non-invasive flexible wearable electrochemical sensor based on Py TS@Ti₃C₂T_x by integrating electrodes with electrodes and flexible substrates.The sensor has good sensitivity,selectivity and stability for uric acid detection,and can effectively avoid the interference of other substances in sweat.We successfully realized the real-time detection of uric acid concentration in human sweat of volunteers by using the sensor.The detection results were consistent with those of the electrochemical workstation,indicating that the sensor can replace uricase for non-invasive detection of uric acid in sweat,and has broad application prospects in health management and disease diagnosis.