Srivastava Sachin K, Hamo Hilla Ben, Kushmaro Ariel, Marks Robert S, Grüner Christoph, Rauschenbach Bernd, Abdulhalim Ibrahim
Department of Electro optic Engineering, Ben Gurion University of the Negev, Beer Sheva 84105, Israel.
Analyst. 2015 May 7;140(9):3201-9. doi: 10.1039/c5an00209e. Epub 2015 Mar 10.
A nanobiosensor chip, utilizing surface enhanced Raman spectroscopy (SERS) on nanosculptured thin films (nSTFs) of silver, was shown to detect Escherichia coli (E. coli) bacteria down to the concentration level of a single bacterium. The sensor utilizes highly enhanced plasmonic nSTFs of silver on a silicon platform for the enhancement of Raman bands as checked with adsorbed 4-aminothiophenol molecules. T-4 bacteriophages were immobilized on the aforementioned surface of the chip for the specific capture of target E. coli bacteria. To demonstrate that no significant non-specific immobilization of other bacteria occurs, three different, additional bacterial strains, Chromobacterium violaceum, Paracoccus denitrificans and Pseudomonas aeruginosa were used. Furthermore, experiments performed on an additional strain of E. coli to address the specificity and reusability of the sensor showed that the sensor operates for different strains of E. coli and is reusable. Time resolved phase contrast microscopy of the E. coli-T4 bacteriophage chip was performed to study its interaction with bacteria over time. Results showed that the present sensor performs a fast, accurate and stable detection of E. coli with ultra-small concentrations of bacteria down to the level of a single bacterium in 10 μl volume of the sample.
一种纳米生物传感器芯片，利用银纳米雕刻薄膜（nSTF）上的表面增强拉曼光谱（SERS），已被证明能够检测出低至单个细菌浓度水平的大肠杆菌（E. coli）。该传感器利用硅平台上高度增强的银等离子体nSTF来增强拉曼谱带，这通过吸附的4-氨基硫酚分子进行了验证。T-4噬菌体被固定在芯片的上述表面上，用于特异性捕获目标大肠杆菌。为了证明不会发生其他细菌的显著非特异性固定，使用了三种不同的额外细菌菌株，即紫色杆菌、反硝化副球菌和铜绿假单胞菌。此外，对另一株大肠杆菌进行的实验以研究该传感器的特异性和可重复使用性，结果表明该传感器可用于不同菌株的大肠杆菌且可重复使用。对大肠杆菌-T4噬菌体芯片进行了时间分辨相差显微镜观察，以研究其随时间与细菌的相互作用。结果表明，本传感器能够在10μl体积的样品中，对超低浓度至单个细菌水平的大肠杆菌进行快速、准确和稳定的检测。
