Polydimethylsiloxane (PDMS) is widely utilized in biomedical devices. However, its inherent hydrophobicity often leads to bacterial colonization, biofilm formation, and the limited durability of conventional surface modifications. Herein, we report a novel and stable surface modification strategy for covalently grafting Rhein, a bioactive compound derived from traditional Chinese medicine, onto PDMS using a tailored silane coupling agent (KH‑550‑Rhein). This covalent immobilization approach effectively suppresses hydrophobic recovery and ensures long‑term surface stability. The resultant PDMS-Rhein exhibited rapid, contact‑active antibacterial effects (> 92% reduction in S. aureus within 1.5 h; > 97% for E. coli within 4 h). Notably, the coating retains high antibacterial efficacy (> 96%) after 6 days of immersion in phosphate‑buffered saline (PBS) and demonstrates excellent reusability over multiple cycles. Moreover, PDMS-Rhein significantly reduced protein adsorption (by 67–82% for BSA, fibrinogen, and lysozyme), resists biofilm formation, and maintains good biocompatibility with hemolysis rates below 5% and fibroblast viability exceeding 80%. This innovative surface modification strategy, utilizing natural products, offers a reliable and translatable strategy for improving the safety and performance of implantable biomedical devices.
Yin et al. (Sun,) studied this question.