Chiral Carbon Dots Differentially Regulate Silkworm Antioxidant Defense and Fibroin Assembly for Stronger Silk

Chirality-dependent biological effects of nanomaterials in vivo remain poorly understood, particularly in complex physiological systems. Here, we investigate this issue by feeding silkworms with electrosynthesized chiral carbon dots (C-CDs: L-/D-CDs) and investigating their impact on both silkworm physiology and silk properties. Our results demonstrate significant chirality-dependent enhancement in silk mechanical performance. D-CDs increased the Young's modulus by approximately 47.0% (9904.67 Pa) and the fracture strength by about 83.4% (526.57 MPa), outperforming L-CDs. This improvement correlates with a substantial increase in the β-sheet content (up to 28.8%). Mechanistically, C-CDs markedly enhanced midgut antioxidant defense, with glutathione levels rising by approximately 20.4% in the D-CDs group. Transcriptomic analysis further revealed altered gene expression with significant enrichment in the endoplasmic reticulum protein processing pathway, providing a molecular link between C-CDs treatment and improved silk performance. This work elucidates the in vivo chirality-specific effects of nanomaterials and establishes a novel strategy for performance-directed engineering of silk.