Real-time reliable detection of adrenocorticotropic hormone using reduced graphene oxide field-effect transistors

Adrenocorticotropic hormone (ACTH), a pivotal regulator in stress response and cortisol production, poses substantial detection challenges owing to its low plasma concentration, susceptibility to fluctuations, and storage-related stability issues. We developed an innovative nano-immunobiosensor platform to overcome these limitations that integrates reduced graphene oxide (RGO) with field-effect transistor (FET) technology. This platform employs anti-ACTH-directed detection to achieve rapid, sensitive, and real-time quantification of ACTH levels. The RGO-FET design capitalizes on the binding capacity of ACTH to pre-arrange anti-ACTH, thereby enhancing target engagement and enabling swift recognition of unlabeled ACTH. The sensor exhibits remarkable sensitivity, detecting ACTH concentrations as low as 0.124 fM in PBS. Furthermore, Bland-Altman analysis comparing our method with existing techniques using clinical samples reveals a high degree of methodological agreement, with 96% of results falling within the 95% confidence interval, underscoring its excellent precision. The principal advantage of this nano-immunobiosensor is its capability for real-time ACTH detection in clinical samples, making it an up-and-coming candidate for a sensitive point-of-care (POCT) diagnostic solution.