  Two-dimensional (2D) materials have been used extensively in various fields
due to their unique physical and chemical properties. Among their diverse
applications, field-effect transistor biosensors (bio-FETs) promise a brilliant
prospect in the fabrication of biodevices for diagnostics especially point of
care (PoC) based biomedical testing. The introduction of 2D nanomaterials as a
sensing platform not only promotes their bioassay process but also provides
label-free, low-cost, real-time, highly sensitive, and selective detection of
different biomolecules. 2D-based bio-FETs are highly desirable for biosensing
applications due to large effective surface area, environment-dependent
conductivity, being easily functionalized, biocompatible and simple fabrication
processes. This review focuses comprehensively on 2D bio-FETs and more on both
dry and wet states. In this regard, these bio-FETs are classified into four
categories including Apta, DNA (Geno), Immuno, and enzymatic biosensors. The
configuration, detection mechanism and electrical signal processing of each
category are discussed in response to different biotargets. Finally, their
promising roles as PoC testing devices for modern medicine are discussed in
biomedical (real) samples.
