In this work, we introduce a one-step strategy that is suitable for continuous flow manufacturing of antimicrobial PDMS materials. The process is based on the intrinsic capacity of PDMS to react to certain organic solvents, which enables the incorporation of antimicrobial actives such as salicylic acid (SA), which has been approved for use in humans within pharmaceutical products. By combining different spectroscopic and imaging techniques, we show that the surface properties of PDMS remain unaffected while high doses of the SA are loaded inside the PDMS matrix. The SA can be subsequently released under physiological conditions, delivering a strong antibacterial activity. Furthermore, encapsulation of SA inside the PDMS matrix ensured a diffusion-controlled release that was tracked by spatially resolved Raman spectroscopy, Attenuated Total Reflectance IR (ATR-IR), and UV-Vis spectroscopy. The biological activity of the new material was evaluated directly at the surface and in the planktonic state against model pathogenic bacteria, combining confocal laser scanning microscopy, electron microscopy, and cell viability assays. The results showed complete planktonic inhibition for clinically relevant strains of Staphylococcus aureus and Escherichia coli, and a reduction of up to 4 orders of magnitude for viable sessile cells, demonstrating the efficacy of these surfaces in preventing the initial stages of biofilm formation. Our approach adds a new option to existing strategies for the antimicrobial functionalisation of a wide range of products such as catheters, wound dressings and in-dwelling medical devices based on PDMS.

在这项工作中，我们引入了一种适用于抗菌 PDMS 材料连续流动制造的一步策略。该过程基于 PDMS 与某些有机溶剂反应的内在能力，这使得抗菌活性物质如水杨酸 (SA) 的结合成为可能，水杨酸 (SA) 已被批准用于人类的医药产品中。通过结合不同的光谱和成像技术，我们表明当高剂量的 SA 加载到 PDMS 基质内时，PDMS 的表面特性不受影响。SA 可以随后在生理条件下释放，提供强大的抗菌活性。此外，将 SA 封装在 PDMS 基质内确保了由空间分辨拉曼光谱跟踪的扩散控制释放，衰减全反射红外 (ATR-IR) 和紫外-可见光谱。结合共聚焦激光扫描显微镜、电子显微镜和细胞活力测定，直接在表面和浮游状态下评估了新材料对模型病原菌的生物活性。结果显示对临床相关菌株的完全浮游抑制金黄色葡萄球菌和大肠杆菌，以及存活的固着细胞减少多达 4 个数量级，证明了这些表面在防止生物膜形成初始阶段的功效。我们的方法为现有的各种产品（例如基于 PDMS 的导管、伤口敷料和内置医疗设备）的抗菌功能化提供了新的选择。