Taylor Allen D, Ladd Jon, Yu Qiuming, Chen Shengfu, Homola Jirí, Jiang Shaoyi
Department of Chemical Engineering, University of Washington, Box 351750, Seattle, WA 98195, USA.
Biosens Bioelectron. 2006 Dec 15;22(5):752-8. doi: 10.1016/j.bios.2006.03.012. Epub 2006 Apr 25.
We report the quantitative and simultaneous detection of four species of bacteria, Escherichia coli O157:H7, Salmonella choleraesuis serotype typhimurium, Listeria monocytogenes, and Campylobacter jejuni, using an eight-channel surface plasmon resonance (SPR) sensor based on wavelength division multiplexing. Detection curves showing SPR response versus analyte concentration were established for each species of bacteria in buffer at pH 7.4, apple juice at native pH 3.7, and apple juice at an adjusted pH of 7.4, as well as for a mixture containing all four species of bacteria in buffer. Control experiments were performed to show the non-fouling characteristics of the sensor surface as well as the specificity of the amplification antibodies used in this study. The limit of detection (LOD) for each of the four species of bacteria in the tested matrices ranges from 3.4 x 10(3) to 1.2 x 10(5) cfu/ml. Detection curves in buffer of an individual species of bacteria in a mixture of all four species of bacteria correlated well with detection curves of the individual species of bacteria alone. SPR responses were higher for bacteria in apple juice at pH 7.4 than in apple juice at pH 3.7. This difference in sensor response could be partly attributed to the pH dependence of antibody-antigen binding.
我们报告了使用基于波分复用的八通道表面等离子体共振（SPR）传感器对四种细菌进行定量和同时检测，这四种细菌分别是大肠杆菌O157:H7、鼠伤寒沙门氏菌猪霍乱血清型、单核细胞增生李斯特菌和空肠弯曲菌。针对pH 7.4的缓冲液、天然pH 3.7的苹果汁、pH调整为7.4的苹果汁中的每种细菌，以及缓冲液中包含所有四种细菌的混合物，建立了显示SPR响应与分析物浓度关系的检测曲线。进行了对照实验，以展示传感器表面的抗污染特性以及本研究中使用的扩增抗体的特异性。在所测试的基质中，四种细菌各自的检测限（LOD）范围为3.4×10³至1.2×10⁵ cfu/ml。在所有四种细菌的混合物中，单个细菌在缓冲液中的检测曲线与单独的单个细菌的检测曲线相关性良好。pH 7.4的苹果汁中细菌的SPR响应高于pH 3.7的苹果汁中的细菌。传感器响应的这种差异部分可归因于抗体 - 抗原结合对pH的依赖性。
