Center for Food Safety and Applied Nutrition (CFSAN), U.S. Food and Drug Administration, 5100 Paint Branch Parkway, College Park, MD 20740, USA.
Center for Food Safety and Applied Nutrition (CFSAN), U.S. Food and Drug Administration, 5100 Paint Branch Parkway, College Park, MD 20740, USA.
Anal Chim Acta. 2015 Sep 10;892:167-74. doi: 10.1016/j.aca.2015.08.029. Epub 2015 Aug 25.
Herein, a rapid and simple gold nanoparticle based colorimetric and dynamic light scattering (DLS) assay for the sensitive detection of cholera toxin has been developed. The developed assay is based on the distance dependent properties of gold nanoparticles which cause aggregation of antibody-conjugated gold nanoparticles in the presence of cholera toxin resulting discernible color change. This aggregation induced color change caused a red shift in the plasmon band of nanoparticles which was measured by UV-Vis spectroscopy. In addition, we employed DLS assay to monitor the extent of aggregation in the presence of different concentration of cholera toxin. Our assay can visually detect as low as 10 nM of cholera toxin which is lower than the previously reported colorimetric methods. The reported assay is very fast and showed an excellent specificity against other diarrhetic toxins. Moreover, we have demonstrated the feasibility of our method for cholera toxin detection in local lake water.
本文提出了一种快速简便的基于金纳米粒子的比色和动态光散射（DLS）测定法，用于灵敏检测霍乱毒素。所开发的测定法基于金纳米粒子的距离依赖性性质，该性质导致在霍乱毒素存在下抗体偶联的金纳米粒子聚集，从而产生可辨别的颜色变化。这种聚集诱导的颜色变化导致纳米粒子的等离子体带发生红移，可通过紫外-可见光谱进行测量。此外，我们还采用 DLS 测定法来监测在不同浓度的霍乱毒素存在下的聚集程度。我们的测定法可以通过肉眼检测到低至 10 nM 的霍乱毒素，这比以前报道的比色方法更低。该报道的测定法非常快速，并对其他腹泻性毒素表现出优异的特异性。此外，我们已经证明了我们的方法在检测当地湖水中毒素的可行性。
