Durable low-friction plasma-polymerized coating for suture needles ensuring safety

• One-step atmospheric-pressure plasma polymerization of TRIAP on curved suture needles. • A 5-minute plasma treatment reduces needle penetration forces by up to 35%. • Coating remains intact over multiple insertions, maintaining low friction. • XPS reveals increased SiO 4 and NH 2 bonds, reducing friction and improving adhesion. • No new volatile compounds are released from coated needles, confirming safety. In wound suturing, the needle and thread are crucial. The ideal surgical needle must be rigid yet flexible, corrosion-resistant, sterile and effectively lubricated to penetrate tissue effortlessly and minimize damage. However, achieving optimal lubrication with current methods, involving cumbersome silicone application and high-temperature curing (2–6 h at 150–250 °C), remains challenging due to the lengthy process. This study explored the use of an atmospheric-pressure plasma jet (APPJ) to rapidly apply a stable, low-friction, one-step coating on curved suture needles. Plasma-polymerized coatings based on N 1 -(3-trimethoxysilylpropyl)diethylenetriamine (TRIAP) were applied. The influence of plasma exposure time was analyzed. After 5 min of plasma treatment, coated needles showed up to a 35 % reduction in penetration forces compared to control needles (silicone-coated). Longer plasma exposure times enhanced the coating’s low-friction and adhesion properties by promoting the formation of SiO 4 and NH 2 bonds, respectively. A minimum treatment time ensured an even coating across the needle surface. Notably, the plasma-polymerized coatings did not introduce any new volatile or semi-volatile compounds, maintaining the needle’s chemical profile. This study demonstrates a faster, more efficient one-step coating process that is scalable to industry, offering consistent performance while significantly reducing suturing forces compared to the conventional silicone coating.