# Advances in Graphene Field Effect Transistors (FETs) for Annine Neurotransmitter Sensing
## 5 Conclusions and Outlook  
Amine NTs play a vital role in the central nervous system by facilitating signal transmission between neurons, which is required for brain-body integration. The absence or dysfunction of these NTs can lead to a spectrum of neurological disorders and illnesses, highlighting the importance of accurate NT sensing for early diagnosis and treatment. Integrating GFETs into amine NT detection technologies represents a considerable leap forward in biosensing. Graphene is a promising material for FET biosensing because of its large specific surface area and strong carrier mobility. However, it lacks a bandgap, which is required for producing high-selectivity GFET sensors. Researchers have made progress toward overcoming this obstacle by using approaches such as surface functionalisation, chemical linker immobilisation, and the incorporation of hybrid materials such as Nafion, gold nanoparticles, and molecularly imprinted polymers. While these methods help to build a bandgap into graphene, they also lower electron mobility. Several electrochemical techniques are available for detecting amine NTs; however, GFET-based biosensors stand out for their high accuracy and lower detection limits. These features enable GFET biosensors to assess concentrations applicable to those found in biofluids, making them more suited for clinical applications. Their increased sensitivity and real-time analytical capabilities make GFET biosensors viable in medical diagnostics and neurochemical research. The quality of graphene has a considerable impact on the performance of GFET biosensors. Current manufacturing technologies, including CVD, may include defects and contaminants that impair sensor performance and increase variability, requiring extensive calibration to assure accuracy across several sensors. Addressing these challenges is crucial to the reliability and scalability of GFET biosensors. Device miniaturising introduces new concerns, including higher power dissipation and associated reliability issues such as electromigration and thermal stress. OFETs are ideal for adaptable, low-power applications in wearable sensors and medical monitoring systems [288, 289]. Addressing device-to-device variability, reducing power consumption, and enhancing device yield are all crucial for functional biosensors [6]. The functionalisation of graphene channels is critical for the successful binding of NT analytes, as influenced by the Debye screening effect, which can conceal charge interactions in binding zones due to its short length in comparison to NT molecules. Carbon nanoribbon structures have been presented as a strategy for increasing sensitivity. Detecting numerous amine NTs simultaneously remains a significant challenge. Future research should concentrate on real-time continuous monitoring, multi-analyte sensing, in vivo detection, and long-term sensor stability, particularly in clinical samples containing high levels of non-target compounds. Non-specific adsorption must be avoided during the development of GFET biosensors through effective surface blocking and sample purification. Long-term stability is critical for commercialising GFET biosensors because it ensures reliable operation in varying environments. Stability analysis throughout time is required to evaluate the biosensors' performance in terms of environmental conditions. The specificity and durability of sensing interfaces are influenced by a variety of characteristics, including anti-interference methods, target molecule accessibility, and an applied electric field [290, 291, 292, 293, 294]. Understanding these parameters is critical when choosing successful functionalisation techniques for amine NT detection applications. Nanomaterial degradation in GFET sensors presents stability problems because they are sensitive to environmental conditions. Biosensors having biological receptors exhibit increased instability, especially in vivo situations containing physiochemical stresses.