Graphene Nanoribbon Enables Enantiomer Discrimination in Chemoresistive Sensors: Computational Insights into Nonequilibrium Effects

In a study published on April 11, 2025, titled Are nonequilibrium effects relevant for chiral molecule discrimination?, researchers demonstrated that non-equilibrium phenomena can significantly influence the detection of enantiomers in sensors. Their computational models revealed electrical current differences up to tens of nanoamperes between enantiomeric pairs, suggesting innovative approaches for enhancing molecular sensing technology.

A computational study demonstrates that a chirality-blind graphene nanoribbon substrate can distinguish enantiomers of chiral amino acids through electrical current differences, amplified by structural fluctuations. Significant current disparities (tens of nanoamperes to microamperes) were observed between enantiomeric pairs using density-functional parametrised tight-binding and nonequilibrium Green functions. The research introduces new mechanical quantities for enantioselective discrimination in molecular sensors, emphasizing binding features and property correlations. These findings highlight the role of nonequilibrium effects in chiral sensing, advancing sensor design principles.

Central to this advancement is the concept of molecular chirality—the property where molecules are non-superimposable mirror images of themselves. Research has revealed that chiral molecules exhibit enhanced spin selectivity, influencing how electrons interact with magnetic fields. This characteristic is pivotal in quantum sensing applications, as it enhances the interaction of molecules with light and magnetic fields, enabling the creation of highly sensitive detectors for trace gases. Such detectors are crucial in environmental monitoring and early disease detection, underscoring the importance of chirality in molecular interactions.

The progress in quantum sensing is significantly driven by computational methods that simulate molecular systems with remarkable accuracy while maintaining efficiency. Techniques such as density functional theory-based tight-binding (DFTB+) and van der Waals density functional (vdW-DF2) are instrumental in predicting molecular behavior under various conditions, facilitating the design of new sensing materials. These methods allow researchers to tailor molecules for specific applications, enhancing sensitivity or selectivity in sensors.

The potential applications of quantum sensing are vast and transformative. In environmental science, these technologies can monitor air quality by detecting harmful gases at extremely low concentrations. In healthcare, they may enable early disease detection through the analysis of biomarkers in bodily fluids. Additionally, advancements in computational design are paving the way for synthetic olfactory receptors, which could revolutionize odor detection across industries such as food safety and security screening.

Quantum sensing represents a significant leap forward in our ability to interact with and understand the molecular world. By harnessing the unique properties of chiral molecules and leveraging advanced computational methods, researchers are unlocking new possibilities for detection and measurement technologies. As this field continues to evolve, it promises sophisticated applications that could profoundly impact various sectors, enhancing our capabilities while opening new avenues for scientific exploration and practical innovation.