A Novel Sensing System For Temperature/pH Detection In The Extracellular Environment

As important environmental parameters of the extracellular environment,temperature and pH are involved in important biochemical processes such as cell differentiation,proliferation,endocytosis and ion transport,and play a key role in the growth state and physiological functions of cells.Therefore,it is important to measure the temperature/pH of the extracellular environment in real time.However,the complexity of the extracellular environment places high demands on the performance and quality of the sensors.In response to the urgent need for new sensors for extracellular environment detection,this paper designs and fabricates a new biocompatible and multifunctional sensor system based on carbonized silk nanofibers,which mainly includes a flexible temperature sensing unit,a micro-nano temperature sensing array,a pH detection module and a signal acquisition and display module.The system exhibits excellent cell compatibility and a wide detection range,providing a new method for the continuous detection of extracellular environment.The main research contents of this paper are as follows:(1)Design and preparation of the sensing system.Firstly,the sensing system consists of two main components:the sensing module and the test platform to meet the specific needs of the extracellular environment.Secondly,the device structure of the temperature sensing unit and pH sensing unit was designed for the changing characteristics of the extracellular environment.Finally,the characterization and testing scheme of the effective layer of the sensor and the sensor device are described.(2)Performance study of sensor devices.The controllable preparation conditions affecting the silk-based nanofibers were mainly investigated,and high-performance temperature sensors were prepared by optimizing the conditions and demonstrated a wide detection range(35.69℃-63.64℃),high sensitivity(1.75%/℃ and 1.48%/℃),good biocompatibility and high interference resistance in practice.Meanwhile,the pH sensor,also based on silk-based carbon nanofiber membranes,not only maintains a linear response in the pH range of 3-11,but can also detect pH changes of up to 0.5pH.The sensing device demonstrates the feasibility and practicality of its application in a real environment.(3)Construction and testing of a cellular environment test platform.This part mainly combines a sensing system with multiple sensing units,an environmental control module and a self-built multi-channel signal acquisition platform to complete the construction of a cell environment monitoring system.Using this system,not only different cell environments(room temperature,35.11℃,41.49℃)can be detected,but also similar outputs(pH=7.3,pH=7.3,pH=7.4)are maintained in the same cell environments.In addition,the sensing system also shows stable outputs in cell environment monitoring,which can be used for continuous monitoring of cell environments.