Domain-Encoded Chirality in Carbon Nanomaterials from Structural Origins and Chiroptical Responses to Biological...

Chirality offers a powerful but underdeveloped design principle for regulating the optical, molecular, and biological behavior of carbon nanomaterials. Unlike small molecules, whose handedness is typically defined by discrete stereocenters, carbon nanomaterials can encode chirality across multiple structural domains, including the carbon framework, chemically accessible surfaces and interfaces, and supramolecular assemblies. These domain-encoded chiralities differ in how they are generated, how they produce chiroptical and electronic responses, and how they are presented at nano-bio interfaces. In this Review, we organize chiral carbon nanomaterials, including carbon dots, graphene quantum dots, graphene oxide derivatives, carbon nanotubes, fullerenes, graphene nanoribbons, and hybrid assemblies, into framework-encoded, surface/interface-derived, and supramolecular chirality. We examine how each category produces circular dichroism, circularly polarized luminescence, fluorescence, and electronic responses, and how these properties influence biointerface interactions and biological or bioanalytical functions. Representative studies span molecular recognition, sensing and imaging, membrane and extracellular-matrix transport, drug delivery, and selected therapeutic effects, including phototherapy, antimicrobial activity, and protein-homeostasis regulation. We further identify major barriers to predictive design, including limited structural control, incomplete assignment of chiroptical origins, insufficient separation of chirality effects from nonchiral physicochemical variables, and limited validation in realistic biological environments. By connecting structural origin, optical expression, and biointerface effect, this Review provides a framework for mechanistically interpreting and designing chiral carbon nanomaterials for biological and bioanalytical applications.