本實驗利用臭氧活化聚苯乙烯材料表面，後以熱聚合的方式將雙離子性高分子poly(sulfobetaine methacrylate) (polySBMA)、不帶電高分子poly(ethylene methacrylate)(polyPEGMA)、帶正電的高分子poly(trimethylammonium methacrylate) (polyTM)及帶負 電的高分子poly(Sulfopropyl methacrylate) (polySA)接枝於表面。高分子於材料表面呈梳狀排列的接枝度將可被有效的控制，並且能展現不同接枝度表面的親水性；而聚苯乙烯組織培養皿上高分子鏈的涵水行為將可藉由表面上高分子接枝度的不同而被控制。於本實驗中，我們藉由定量出高分子於材料表面的覆蓋量，而去探討高分子覆蓋量影響細菌於表面貼附且產生生物膜的關係，並且進一步比較纖維母細胞與細菌，因生物分子表面與材料表面間的靜電作用或親疏水性作用，而於材料表面的貼附行為。而經由原子自由基轉移法而將高分子完美覆蓋於表面的改質材料與未改質的材料將被應用作於高分子材料抗菌能力的參考與對照。短時間(三小時)與長時間(二十四小時)於材料上培養的兩株細菌(革蘭氏陽性菌:表皮葡萄球菌與革蘭氏陰性菌:大腸桿菌)與纖維母細胞，將在37℃下進行靜態與動態的培養，以觀察在兩培養系統中生物分子的貼附情形。結果顯示，纖維母細胞在表面為帶電高分子(polySA 與polyTM)接枝的材料上，尤其是帶正電的材料表面，將無法減少貼附的數量，而在不帶電高分子(polyPEGMA)與電中性高分子(polySBMA) 接枝的材料上，將可有效抑制纖維母細胞的貼附；但由細菌貼附於改質材料表面的結果來看，除了帶正電polyTM 接枝的材料表面之外，其餘帶負電polySA、不帶電polyPEGMA 與電中性polySBMA 接枝的表面都能有效的隨著表面接枝度增加而提升抗菌貼附能力，其最大的因素便來自於帶負電的細菌表面與改質材料間的靜電作用所致。然而，由實驗結果觀察到，在短/長時間細菌貼附實驗中，表皮葡萄球菌於靜態培養系統中在材料表面所增加的貼附數量比大腸桿菌來得多；而在動態培養系統中，表皮葡萄球菌由材料表面的脫附數量又會較大腸桿菌的數量來得多。由以上的結果顯示，表皮葡萄球菌在材料表面貼附聚集的速度比大腸桿菌來得快，而大腸桿菌會較難由已貼附的表面去除，原因來自於大腸桿菌的細胞表面較表皮葡萄球菌來得更為親水，因而造成如此差異。 In this study, polystyrene surfaces were grafted with zwitterionic polymer brushes of poly(sulfobetaine methacrylate) (polySBMA) ,non-charged polymer brushes of poly(ethylene methacrylate) (polyPEGMA), positive-charged polymer brushes of poly(Sulfopropyl methacrylate) (polySA) and negative-charged polymer brushes of poly(trimethylammonium methacrylate) (polyTM). These were prepared via surface-activated ozone treatment and thermally induced graft copolymerization.Surface packing property of polymer brushes exhibited controllable packing and showed different surface hydrophilicity. The hydration behavior of polymer chains on the resulting TCPS plates can be controlled by the grafting density of polymer on the TCPS surface. In this study, we quantify how surface packing densities of polymer affect bacterial adhesion and biofilm formation on the modified surfaces, and then compare fibroblast cell and bacteria attachment on the material surface owing to electrostatic interaction , or hydrophilic and hydrophilic interaction, between the biological molecules and material surfaces. A well-packed polymer grafted surface via surface-initiated atom transfer radical polymerization (ATRP) was also studied for comparison of anti-bacterial and un-modified TCPS surface was chosen as reference. The short-term adhesion (3 h) and the long-term accumulation (24 h) of two bacterial species (Gram-positive Staphylococcus epidermidis and Gram-negative Escherichia coli), and fibroblast cells on these surfaces in static or dynamic incubation at 37oC to observe the biological molecules attached on the surfaces of modified materials in two culture system. The relative cell adhesion on the surface grafted by charged polymer(polySA and polyTM) were both not reduced, especially for positive-charged polyTM、non-charged polymer (polyPEGMA) and zwitterionic neutral polymer (polySBMA) will be effectively suppressed. Relative bacterial adhesion on the surface, except for positive-charged polyTM,negative-charged polySA、non-charged polymer (polyPEGMA) and zwitterionic neutral polymer (polySBMA) was effectively reduced with increasing surface packing densities of polymer brush grafted on the TCPS surface. The major reason was responsible for the electrostatic interaction between negative charge of bacteria surface and the material surfaces. However, the increasing amount of Staphylococcus epidermidis short/long-term accumulation on the modified materials in the static incubation was more than Escherichia coli, and in the dynamic incubation, the detachable numbers of Staphylococcus epidermidis was also larger than Escherichia coli. Above results was shown the attachment rate of Staphylococcus epidermidis was faster than Escherichia coli, and Escherichia coli were hard to remove once they attached on the materials because of their cell surface was more hydrophilic than Staphylococcus epidermidis.
