Improving anti‐Gram‐positive‐bacterial performance and osteogenesis for zinc alloy via mussel mimetic polydopamine with non‐antibiotic lysozyme and parathyroid hormone

In this work, a novel coating with a non‐antibiotic agent for inhibiting Gram‐positive bacteria and promoting osteogenesis was prepared on zinc‐aluminium alloy (ZA6‐1) via mussel mimetic polydopamine (PDA) containing lysozyme (LYS) and parathyroid hormone (PTH). The results indicate that as‐deposited coatings can efficiently decrease the degradation rate of ZA6‐1 from 0.52 to 0.16 mm/year, and the addition of LYS weakens the coating resistance, while the addition of PTH enhances the coating resistance. In spite that no obvious inhibition of Escherichia coli is observed, the coated zinc alloys show good in vitro antibacterial performance against Staphylococcus aureus. Compared with ZA6‐1 zinc alloys, the increase of antibacterial efficacy reaches 86.9%–90.1%. Furthermore, the lower hydrophilicity (26.4°), higher osteoblast cell viability (>100%), good osteoblast cell morphology and better osteoblast cell differentiation (ALP = 107.7%) for PDA‐LYS/PTH coated samples support that as‐prepared coating is promising for modifying biodegradable zinc implants.