Writing and Reading Chirality at the Nanoscale: Chiral Nanopaint and Chiroptical Entropy Harvesting

Breaking spatial symmetry at the nanoscale offers a powerful dimension of recognition. However, its broader potential is bottlenecked by material-specific syntheses restricting versatility, and an exclusive focus on writing (imparting) chirality without strategies to read it as functional information. Here, we present a unified framework for both writing and reading nanoscale chirality.

First, we introduce chiral nanopaint, a universal interfacial strategy for writing chirality onto diverse achiral nanomaterials without altering their core properties. D-handed iron oxide nanoparticles (IONPs) exhibited approximately 50 percent higher cellular uptake and a 4-fold greater tumor reduction during in vivo magnetic hyperthermia via enantiospecific receptor binding. Similarly, D-lipid nanoparticles (LNPs) improved mRNA expression by 5.3-fold. Beyond biology, painted 2D Ti₃C₂T_x MXenes achieved broadband chiroptical activity, enabling circularly polarized light (CPL)-responsive, ternary multidirectional optomechanical transducers.

Second, we present a chiroptical entropy harvester to read local chirality from defect-driven, stochastic block copolymer nanopatterns. By analyzing chiroptical hotspots via Raman optical activity (ROA), structural asymmetry is digitized into a ternary state system (+1, 0, -1). This extracts physically unclonable random sequences, improving information density by 58.5 percent over conventional binary harvesters and demonstrating robust unpredictability against machine-learning prediction models.

Ultimately, this unified approach establishes symmetry breaking as a universal design parameter, advancing next-generation nanomedicines, optomechanics, and hardware security devices.