Labib Mahmoud, Hedström Martin, Amin Magdy, Mattiasson Bo
Department of Biotechnology, Lund University, P. O. Box 124, 221 00, Lund, Sweden.
Anal Bioanal Chem. 2009 Mar;393(5):1539-44. doi: 10.1007/s00216-008-2559-x. Epub 2008 Dec 19.
A sensitive method for the detection of staphylococcal enterotoxin B (SEB) using a flow-injection capacitive biosensor is presented. SEB was purified from a crude culture filtrate of Staphylococcus aureus through three chromatographic steps. The first two steps were based on ion-exchange chromatography, and the last step was carried out on a gel filtration column. The SEB recovery values after the purification stages were 88%, 74%, and 12%, respectively. A horseradish peroxidase labeled antistaphylococcal enterotoxin B was prepared by the periodate method and was further employed in a sandwich-enzyme-linked immunosorbent assay (ELISA) for the determination of SEB concentrations in different samples obtained during the processing of the crude filtrate. The capacitive biosensor could detect SEB concentrations as low as 0.3 pg ml(-1) with a linearity ranging from 2.8 pg ml(-1) to 2.8 ng ml(-1) under optimized conditions. The response time was about 10 min. A good agreement was achieved between the developed capacitive biosensor system and ELISA as a reference method for detection of SEB levels in different purification samples. The newly developed sensor has the benefits of simplicity, high sensitivity, and multiple use capability.
介绍了一种使用流动注射电容式生物传感器检测葡萄球菌肠毒素B（SEB）的灵敏方法。通过三个色谱步骤从金黄色葡萄球菌的粗培养滤液中纯化SEB。前两步基于离子交换色谱，最后一步在凝胶过滤柱上进行。纯化阶段后的SEB回收率分别为88%、74%和12%。采用高碘酸盐法制备了辣根过氧化物酶标记的抗葡萄球菌肠毒素B，并将其进一步用于夹心酶联免疫吸附测定（ELISA），以测定粗滤液处理过程中获得的不同样品中的SEB浓度。在优化条件下，电容式生物传感器能够检测低至0.3 pg ml⁻¹的SEB浓度，线性范围为2.8 pg ml⁻¹至2.8 ng ml⁻¹。响应时间约为10分钟。所开发的电容式生物传感器系统与作为检测不同纯化样品中SEB水平参考方法的ELISA之间取得了良好的一致性。新开发的传感器具有简单、高灵敏度和可多次使用的优点。
