The Application Of Organic Thin-Film Transistor In Early Cancer Diagnosis

Scientific research for human’s health plays an irreplaceable role in our social life.For instance,the development of accurate and reliable method has received significant attention in early cancer diagnosis.Organic thin-film transistors（OTFTs）have attracted extensive attention due to facile preparation,inherent biocompatibility,fast and real-time signal response,etc.However,there still exist many problems,such as efficient immobilization of sensitive probes,sensitive and reliable determination of biomarkers,and promotion of practical application.Herein,this dissertation summarized the composition,classification,mechanism and construction strategies of OTFT-based biosensors.The main contents are as following:1.A kind of stable and high-performance water-gated OTFT-based biosensor was developed by using the polymer as the active layer.Specifically,alpha-fetoprotein antibodies（anti-AFP）as sensitive probes were immobilized by direct absorption for alpha-fetoprotein（AFP）determination.The whole process was completed in 45 min,and the sensitivity was greatly improved with the limit-of-detection（2.14 p M）,lower than the cut-off value in clinical early cancer diagnosis.2.The 2,6-bis（4-formylphenyl）-anthracene（BFPA）material was modified on the sensing surface by vacuum deposition.Afterwards,stable and large-area immobilization of anti-AFP were achieved via a covalent interaction,which enables ultrasensitive determination of AFP at f M level.Besides,the device exhibited improved accuracy through monitoring changes of the source-drain current(△I_SD)and changes of threshold voltage(△V_TH)as electrical signals.3.The reliability was greatly improved by simultaneous monitoring of AFP and carcinoembryonic antigen（CEA）in early cancer diagnosis.In this section,a facile functionalization strategy was developed by blending glutaraldehyde with organic semiconductors,which can effectively inhibit the gelation of the solvent and improve the device performance.Besides,functional groups were introduced for efficient immobilization of antibodies,enabling rapid detection of two target biomarkers.4.The arraying of OTFTs was a key aspect to promote the clinical application with statistical data in the future.Herein,the pillar[5]arene-COOH was integrated as a signal amplifier with OTFTs,and the limit-of-detection can reach a M level.Afterwards,the OTFT-based biosensor array was divided into several regions for simultaneous determination of AFP,CEA and prostate antigen（PSA）,which provides a new way for high-throughput screening of diseases.