Construction Of Indium Gallium Zinc Oxide Sensor For The Diagnosis Of Bladder Cancer

Bladder cancer is one of the most common urogenital malignant tumors with extremely high mortality.Currently,cystoscopy is the gold standard for clinical diagnosis of bladder cancer,but is an uncomfortable and invasive procedure,even associated with urinary tract infections and different levels of hematuria within a few days of testing.Now some of the metabolites in urine have been identified as biomarkers of bladder tumor.In this regard,the development of a urine-based bladder cancer marker biosensor has brought hope for the painless and noninvasive diagnosis of bladder cancer.However,because of the extremely low biomarker content in urine and the high background signals,the achievement of high sensitivity and accuracy detection of bladder cancer is significantly limited.Nowadays,biosensors have shown great application value in social each profession and the domain.Biosensor exhibits the advantages of fast,cheap and convenient,providing a new solution for the detection of cancer biomarkers.Recently,biosensors based on field effect transistors(FETs)have been developed rapidly because of their extraordinary electronic characteristics,such as fast response,miniaturization and circuit integration.Nano-biosensor devices composed of FETs and functional molecules combines the advantages of biomolecule specific recognition and transistor signal amplification perfectly,and it can simultaneously serve as a sensor and an amplifier,causing an obvious channel current change under a tiny voltage variation,in which high sensing sensitivity can be attained.Among them,FET based on indium gallium zinc oxide has become a research hotspot of transistor biosensors due to the features of simple preparation process,large-scale fabrication,array formation and high signal stability,offering opportunities for highly sensitive detection of trace cancerspecific molecules in body fluids.In this study,we constructed high performance indium gallium zinc oxide thinfilm transistors(IGZO TFTs).The electronic performance and stability of IGZO TFTs is systematically investigated.On that basis,recognition molecules functionalized IGZO TFT biosensors were constructed to achieve highly sensitive and selective detection of trace bladder cancer biomarkers in urine.With this biosensor,we also distinguished the urine samples from bladder cancer patients and healthy donors.The detailed contents are described as follows:(1)An indium gallium zinc oxide thin film was deposited on a silicon substrate by magnetron sputtering,and the IGZO TFT with high performance was further constructed.Our prepared IGZO film is flat and smooth,and this uniformity ensures the reproducibility and reliability of IGZO TFTs biosensor.In addition,the IGZO TFTs show excellent electrical performance,such as high field effect mobility,high on/off current ratio,and tiny leakage current,which shows that the IGZO TFTs have the potential to be constructed as a biosensor for biomedical applications.(2)By modifying antibody molecules with specific recognition capabilities,a high stability transistor biosensor was constructed for high sensitivity and selectivity detection of trace amount of bladder cancer biomarkers.The limit of detection,sensitivity and reproducibility of IGZO TFTs biosensor were comprehensively analyzed.The application of IGZO TFTs biosensor for the detection of real urine samples was investigated,and the results show that our device can be applied to differentiate the urine samples from bladder cancer patients and healthy donors.