A crucial factor in the pathogenesis of orthopedics associated infections is that bacteria do not only colonize the implant surface but also the surrounding tissues. This study aimed to engineer an antimicrobial release coating for stainless steel (SS) surfaces, to impart them with the ability to prevent Staphylococci colonization. Chlorhexidine (CHX) was immobilized using two polydopamine (pDA)-based approaches: a one-pot synthesis, where CHX is dissolved together with dopamine before its polymerization; and a two-step methodology, comprising the deposition of a pDA layer to which CHX is immobilized. To modulate CHX release, an additional layer of pDA was also added for both strategies.

Immobilization of CHX using a one-step approach yielded surfaces with a more homogenous coating and less roughness than the other strategies. The amount of released CHX was lower for the one-step approach, as opposed to the two-step approach yielding the higher release, which could be decreased by applying an outward layer of pDA. Both one and two-step approaches provided the surfaces with the ability to prevent bacterial colonization of the surface itself and kill most of bacteria in the bulk phase up to 10 days. This long-term antimicrobial performance alluded a stable and enduring immobilization of CHX. In terms of biocompatibility, the amount of CHX released from the one-step approach did not compromise the growth of mammalian cells, contrary to the two-step strategy. Additionally, the few bacteria that managed to adhere to surfaces modified with one-step approach did not show evidence of resistance towards CHX.

Overall data underline that one-step immobilization of CHX holds great potential to be further applied in the fight against orthopedic devices associated infections.

骨科相关感染的发病机理中的关键因素是细菌不仅定植在植入物表面，而且定居在周围组织。这项研究旨在设计一种用于不锈钢（SS）表面的抗菌释放涂层，使它们具有预防葡萄球菌定植的能力。氯己定（CHX）使用两种基于聚多巴胺（pDA）的方法固定化：一锅合成，其中CHX与多巴胺一起溶解，然后聚合。以及两步法，包括沉积固定有CHX的pDA层。为了调节CHX的释放，还为这两种策略增加了一层pDA。

使用一步法固定CHX可以得到比其他策略更均匀的涂层和更小的粗糙度的表面。一步法产生的CHX释放量较低，而两步法产生的释放量较高，通过施加向外的pDA层可以降低释放量。一步骤和两步方法都为表面提供了防止表面自身细菌定居并杀死散装相中大多数细菌的能力（最多10天）。这种长期的抗菌性能暗示了CHX的稳定和持久固定。在生物相容性方面，与两步策略相反，一步法释放的CHX量不会损害哺乳动物细胞的生长。另外，

总体数据表明，一步固定CHX具有巨大的潜力，可以进一步应用于对抗骨科器械相关感染。