Biological functionalization of a sol-gel coating for the mitigation of microbial-induced corrosion
Biological functionalization of a sol-gel coating for the mitigation of microbial-induced corrosion
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DOI：
10.1002/adfm.200600493
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发表时间：
2008-01-24
影响因子：
19
通讯作者：
Earthman, James C.
中科院分区：
文献类型：
--
作者：
Akid, Robert;Wang, Heming;Earthman, James C.
向水系统中添加杀生物剂是限制或减轻导致微生物诱导腐蚀（MIC）发展的表面生物膜形成的最直接尝试，该过程每年花费工业数百万英镑。该方法的功效取决于a）将杀生物剂递送至所有水-金属基质相互作用位点和B）杀生物剂保持活性，从而防止生物膜发展/生长。在供水系统中添加防污杀生物剂或在油漆中添加抗真菌剂，对环境有不利影响，例如，三丁基锡对水生生物有毒。作者目前正在寻求的另一种无毒方法涉及将生物活性试剂定位在金属基底附近。在这种情况下，通过合成混合功能溶胶-凝胶涂层并将合适的非致病性生物组分封装在溶胶-凝胶基质内来实现定位。营养细菌或孢子的溶胶-凝胶涂层内的分布已被证实使用各种显微镜技术。极化电阻、阻抗谱和电化学噪声形式的电化学数据都表明，在溶胶-凝胶涂层中存在脆弱拟杆菌或多粘拟杆菌导致耐腐蚀性改善至少是等效非生物涂层的10倍。在潮汐河口环境中进行的为期六个月的现场试验测试证实了这一改进。使用对照溶胶-凝胶涂层浸没在含有自由悬浮的多粘立克次体的营养贫乏的人工海水中的比较试验显示，与不存在内生孢子的对照样品相比没有显著的改善。
The addition of biocides to water systems has been the most direct attempt to limit or mitigate the formation of surface biofilms that lead to the development of microbial-induced corrosion (MIC), a process that costs industry millions of pounds annually. The efficacy of this approach is dependent upon a) the biocide being delivered to all water-metal substrate interaction sites and b) the biocide remaining active, therein preventing biofilm development/growth. Anti-fouling biocide additions to water supplies, or anti-fungal additives in paints, have an adverse impact upon the environment, for example, tri-butyl tin is toxic to aquatic life. An alternative non-toxic approach currently being pursued by the authors involves localizing a biologically active reagent close to the metal substrate. Localization in this case is achieved by synthesizing a hybrid functional sol-gel coating and encapsulating a suitable non-pathogenic biological component within the sol-gel matrix. Distribution within the sol-gel coating of vegetative bacteria or spores has been confirmed using various microscopy techniques. Electrochemical data in the form of polarization resistance, impedance spectroscopy, and electrochemical noise all show that the presence of either P. fragi or P. polymyxa within a sot-gel coating leads to a corrosion resistance improvement at least 10 times that of an equivalent abiotic coating. Confirmation of this improvement is derived from six months of field trial testing conducted in a tidal estuarine environment. Comparative tests that use a control sol-gel coating immersed within nutrient poor artificial seawater that contained freely suspended R polymyxa reveal no marked improvement over a control sample in the absence of the endospores.