医用涤纶材料表面类金刚石涂层的表面自由能参数对细菌黏附的影响

The Effect of Surface Free Energy Parameters of Diamond-like Carbon Films Deposited on Medical Polyethylene Terephthalate on Bacterial Adhesion

采用乙炔等离子体浸没离子注入与沉积技术(P III-D)在医用涤纶缝合环材料表面沉积了一层类金刚石(DLC)薄膜。细菌黏附实验的结果证明沉积了类金刚石薄膜后的表面对五种细菌——金黄色葡萄球菌(S taphy lococcus aureus,SA)、表皮葡萄球菌(S taphy lococcus ep iderm id is,SE)、大肠杆菌(E scherich ia co li,EC)、绿浓杆菌(P seudom onas aerug inosa,PA)和白色念珠菌(C and ida a lb icans,CA)的黏附均有明显的减少(P<0.05)。计算细菌与材料之间的黏附自由能ΔFadh表明:细菌对PET表面的黏附自由能为负值,而细菌对DLC表面的ΔFadh>0,因此细菌对DLC表面黏附过程难于发生,即使黏附也是可逆的。

Diamond-like carbon （DLC） films were deposited by acetylene plasma immersion ion implantationdeposition （PIII-D） on biomedical polyethylene terephthalate （PET）. The capacities of Staphylococcus aureus （SA）, Staphylococcus epidermidis （SE）, Escherichia coli （EC）, Pseudomonas aeruginosa （PA） and Candida albicans （CA） for adhesion to PETs are quantitatively determined by the plate counting and Gamma-ray counting of ^125I radio labeled bacteria in vitro. The results indicate that the capacities of five types of bacteria for adhesion to PETs are all suppressed by C2H2 PIII-D （P〈0. 05）. The surface energy components of the various substrates and bacteria are calculated based on measurements in water, formamide and diiodomethane and Lifshitz-van del Waals/acid-base approach （LW-AB）. The surface free energies obtained are used to calculate the interracial free energies of adhesion （△Fadh） of five kinds of bacteria on various substrates, and the results show that it is energetically unfavorable for bacterial adhesion to the DLC films already deposited on PET by C2H2 PIII-D.