Jain Prashant, Pradeep T
Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai 600036, India.
Biotechnol Bioeng. 2005 Apr 5;90(1):59-63. doi: 10.1002/bit.20368.
Silver nanoparticles can be coated on common polyurethane (PU) foams by overnight exposure of the foams to nanoparticle solutions. Repeated washing and air-drying yields uniformly coated PU foam, which can be used as a drinking water filter where bacterial contamination of the surface water is a health risk. Nanoparticles are stable on the foam and are not washed away by water. Morphology of the foam was retained after coating. The nanoparticle binding is due to its interaction with the nitrogen atom of the PU. Online tests were conducted with a prototypical water filter. At a flow rate of 0.5 L/min, in which contact time was of the order of a second, the output count of Escherichia coli was nil when the input water had a bacterial load of 10(5) colony-forming units (CFU) per mL. Combined with the low cost and effectiveness in its applications, the technology may have large implications to developing countries.
通过将普通聚氨酯（PU）泡沫在纳米颗粒溶液中放置过夜，可将银纳米颗粒包覆在泡沫上。反复洗涤并风干后可得到包覆均匀的PU泡沫，其可用作饮用水过滤器，因为地表水的细菌污染会带来健康风险。纳米颗粒在泡沫上很稳定，不会被水冲走。包覆后泡沫的形态得以保留。纳米颗粒的结合是由于其与PU中的氮原子相互作用。使用原型水过滤器进行了在线测试。在流速为0.5升/分钟（接触时间约为一秒）的情况下，当输入水中每毫升细菌载量为10⁵菌落形成单位（CFU）时，大肠杆菌的输出计数为零。鉴于该技术成本低且应用有效，它可能对发展中国家有重大影响。
