Distinct Chiral Nanostructures of Graphene Quantum Dots Govern Divergent Passive and Active Enantioselective Transport across Biological Membranes

ABSTRACT Chirality in two-dimensional nanomaterials provides a powerful lever to control biological interfaces, yet the structural origins of nanoscale chirality remain poorly understood. Here, we systematically investigate chiral ligand modulated graphene quantum dots (GQDs) and reveal how ligand stereochemistry and edge chemistry modulate the formation of diverse chiral or achiral nanostructures. Spectroscopy, microscopy, and density functional theory with ring-puckering analysis identified six structural motifs, twisted-, twisted-boat, saddle-shaped, hybrid, unbuckled, and random. Among these, twisted-, twisted-boat, and saddle-shaped GQDs exhibited genuine nanoscale structural chirality, while unbuckled, hybrid, and random conformations lacked organized distortion. Importantly, structural chirality governed passive permeation into biological membrane (e.g. lipid membrane of extracellular vesicles), whereas achiral variants relied mainly on hydrophobic interactions. In contrast, active transport across biological membrane (e.g. endocytosis) is insensitive to nanoscale structural chirality but strongly influenced by chiral ligand identity and transporter recognition. Collectively, these results establish chiral ligand conjugation as a modular route to program both chiral and achiral motifs in graphene nanostructures and highlight nanoscale structural chirality as a design principle for engineering bio-nano interactions.