Urinary VOC Sensing And Non-invasive Diagnosis Of Diseases Based On A Microchamber-integrated Electronic Nose

Biomarkers are important biological indicators in medical diagnosis and treatment.Various biomarkers have been recently explored and researched for healthcare.Currently,scientists have discovered that oxidative stress,inflammation,and cell metabolism are related to the generation of volatile organic compounds(VOC).VOC is regarded as a systemic and local biomarker that might offer distinctive information about individual metabolism and health.Therefore,the identification of VOC can suggest fresh approaches to non-invasive health monitoring and illness diagnosis.The traditional technologies based on chromatography and/or mass spectrometry are mainly used for detecting VOC.But they are limited by sophisticated pre-processing,huge instrument volume,time requirements,and high cost.The electronic noses(i.e.,e-noses)have been used to rapidly identify VOC and explore their application prospects in healthcare.Although some e-noses can quickly identify complex VOC for disease diagnosis,there are still limitations such as high cost,poor performance and/or bulky instrument.Therefore,creating a low-cost,high-performance,and portable intelligent e-nose system for healthcare is still a long-term challenge.Based on the key scientific issues of non-invasive disease diagnosis of artificial intelligence e-noses,this article is based on the basic proposition of “urinary VOC sensing and non-invasive diagnosis of diseases based on a microchamber-integrated electronic nose”.A series of high-performance and differentiated porous MXene framework(MFs)gas-sensitive materials were synthesized for the first time using the modular assembly strategy,offering a rich material foundation for the creation of gas sensor arrays.The method not only widen the application of MXene nanomaterials on the gas sensor array,but also reduces the synthesis time and cost of the material;in addition,laser-induced graphene interfingered electrode(LIGIE)arrays with planar structure were large-scale fabricated through laser-writing technology to load porous MFs,which successfully fulfill the demand for fabricating low-cost gas sensor arrays.The MFs-based gas sensor array was further integrated into a microchamber to construct a compact microchamber integrated e-nose(i.e.,the MHMF e-nose).Finally,a portable urinary VOC point-of-care detection(POCT)platform with the MHMF enose as the core was built,combined with machine learning algorithms to realize highly accurate identification of multiple diseases.This paper is divided into three parts,detailed as follows:Chapter 1.IntroductionFirstly,the importance of VOC detection and recognition is summarized from three parts: the source and release of human VOC,the detection method of VOC and the application prospect of VOC.It then focuses on the use of e-noses in the detection and recognition of VOC,including gas sensing material and structured design of gas sensor array,signal processing,pattern recognition,and application.Finally,the significance and main content of this paper are introduced.Chapter 2.The systhesis porous MXene frameworks and VOC gas sensing application based on the modular assembly strategyIn this study,metal ions,ligands,and dopamine(DA)as the starting raw material are chosen.By adjusting the type of metal ions and ligands and the addition order of three raw materials,bionic hybrid modules with differentiated structures and performances are synthesized.Then,they are able to be assembled with the MXene nanosheets to form a series of porous MFs materials,that is modular assembly strategy.Porous MFs contains two parts,of which the bionic hybrid module is used for VOC gas recognition,while MXene nanosheets are used for electronic conduction.The MFs synthesized by this strategy not only has good sensitivity characteristics,but also the synthesis method is simple,which is conducive to reducing costs,and also providing more materials options for the construction of the gas sensor array.Chapter 3.Microchamber-integrated E-nose for the detection of urinary VOC and non-invasive of diseasesIn this study,high-performance porous MFs synthesized by the modular assembly strategy are loaded onto the LIGIE array.MFs-based gas sensor array assembled into the laser-engraved microchamber for building a MHMF e-nose.Our MHMF e-nose has high identification ability to perceive and distinguish complex VOC at the same time.Since the MHMF e-nose is a plug-and-play miniature module,it can be further assembled into a portable POCT platform for real-time monitoring of VOC in clinical urine samples.The platform combined machine learning algorithms is capable of identifying multiple diseases,with an average accuracy rate of 91.7%,which is expected to be used for early diagnosis,course monitoring,and related research on diseases.