Accurate Diagnosis of Pancreatic Ductal Adenocarcinoma by Detection of miRNA‐196a Biomarker in Exosome Using Solution‐Gated Graphene Transistor with Antifouling Design

The accurate diagnosis of pancreatic ductal adenocarcinoma (PDAC) suffers low specify, and low sensitivity of biomarker detection. In complex biological fluid environments, nonspecific adsorption is prevalent, posing challenges to the accurate detection of biomarkers at low concentrations. Herein, a highly sensitive and selective solution-gated graphene transistor (SGGT) is fabricated for the detection of miRNA-196a in exosomes to diagnose PDAC. The antifouling modification on the surface of the gate electrode is employed through using bovine serum albumin as a common sealing agent and poly adenine (polyA₈) to enhance surface hydrophilicity. The effect of background noise on the detection is effectively reduced. The limit of detection reached 1.82 × 10^-19 m without the need for labeling or amplification, and the detection time is within 25 min. The clinical experiments verify that receiver operating characteristic curve values of miRNA-196a detection in clinical diagnosis are higher than that of carbohydrate antigen 19-9 biomarker, and are as high as 0.98. The miRNA-196a detection can well distinguish PDAC from non-PDAC subjects. The SGGT sensor platform demonstrates significant potential for the accurate detection and diagnosis of PDAC within the milieu of complex biological samples.