Mourtas Spyridon, Diamanti Georgia, Foka Antigoni, Dracopoulos Vassileios, Klepetsanis Pavlos, Stamouli Vasiliki, Spiliopoulou Iris, Antimisiaris Sophia G
J Biomed Nanotechnol. 2015 Dec;11(12):2186-96. doi: 10.1166/jbn.2015.2160.
Stainless steel surfaces were processed by gold deposition in order to immobilize tobramycin-loaded liposomes which were functionalized on their surface with thiol-groups (through maleimide (MAL) derivatization with thiols). After optimizing the tobramycin loading in liposomes (LIPs), and the immobilization of THIOL-MAL-functionalized LIPs on gold-sputtered surfaces, the coated surfaces were challenged with two reference Staphylococcus epidermidis strains: ATCC 35984 (slime-positive) and ATCC 12228 (slime-negative), in order to measure the degree of surface protection from biofilm formation. Moreover, the effect of the reference and two well characterized clinical S. epidermidis strains on the integrity of LIPs (composed of PC or DSPC) was evaluated, in order to investigate whether specific interactions between LIPs and bacteria occur, and if they are affected by LIP membrane composition and/or bacterial strain type. Bacteria growth on surfaces is substantially inhibited by TOBR-loaded-LIP immobilization, especially in the case of the non-biofilm forming bacterial strain. Gold sputtered surfaces were moderately (albeit significantly) protected, from both reference strains tested (compared to bare surfaces). Interestingly, LIP integrity is significantly decreased in the presence of bacteria (at specific lipid/bacteria ratios); the biofilm-forming bacteria being most potent for LIP disruption, whereas, less rigid liposomal membranes (PC) are affected more compared to rigid (DSPC) ones. The clinical strains are also reactive against LIP. This interaction indicates a potential for triggered release of LIP-encapsulated drugs in presence of biofilm-forming bacteria, therefore LIP encapsulation/immobilization may be envisioned as a potential platform technology for triggered antimicrobial therapy.
对不锈钢表面进行金沉积处理，以固定负载妥布霉素的脂质体，这些脂质体在其表面通过硫醇基团进行功能化修饰（通过硫醇与马来酰亚胺（MAL）衍生化）。在优化脂质体（LIPs）中妥布霉素的负载量以及将硫醇-MAL功能化的LIPs固定在溅射金表面后，用两种表皮葡萄球菌参考菌株对涂覆表面进行挑战：ATCC 35984（产黏液阳性）和ATCC 12228（产黏液阴性），以测量表面对生物膜形成的保护程度。此外，评估了参考菌株和两种特征明确的临床表皮葡萄球菌菌株对LIPs（由PC或DSPC组成）完整性的影响，以研究LIPs与细菌之间是否发生特异性相互作用，以及它们是否受LIP膜组成和/或细菌菌株类型的影响。负载妥布霉素的LIP固定化可显著抑制表面细菌生长，尤其是对于非生物膜形成细菌菌株的情况。与未处理的表面相比，溅射金表面受到两种测试参考菌株的保护程度适中（尽管具有显著差异）。有趣的是，在存在细菌的情况下（在特定脂质/细菌比例下），LIP的完整性显著降低；生物膜形成细菌对LIP破坏的作用最强，而与刚性（DSPC）脂质体膜相比，刚性较小的脂质体膜（PC）受到的影响更大。临床菌株对LIP也有反应。这种相互作用表明在存在生物膜形成细菌的情况下，LIP包封药物有触发释放的潜力，因此LIP包封/固定化可被设想为一种触发抗菌治疗的潜在平台技术。
