A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of The Russian Academy of Sciences, Leninsky Prospect 33, Moscow, 119071 Russia.
A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of The Russian Academy of Sciences, Leninsky Prospect 33, Moscow, 119071 Russia.
Biosens Bioelectron. 2016 Dec 15;86:575-579. doi: 10.1016/j.bios.2016.07.027. Epub 2016 Jul 9.
Immunoreagents with good results in the competitive enzyme-linked immunosorbent assay are often unable to provide the required detection limit in the traditional competitive immunochromatographic assay. The solution may be either the production of new reagents or improving the test strip. In the latter case, the assay is often performed stepwise using additional liquid reagents, but this is a significant drawback for practical use. We introduce a test strip made as a dry chemical device that still provides the two-step immunochemical interactions - formation of a complex of specific antibodies with an antigen and its detection by a conjugate of antispecies antibodies with a nano-sized label. Analysis with this test strip is similar to that with ordinary test strips and requires no additional reagents and manipulation. The use of specific antibodies and marker as two separate components allows to improve the analytical parameters. The new test significantly lowers the limit of detection, making it possible to use antibodies previously ineffective in immunochromatography. The proposed approach was tested by determining zearalenone and aflatoxin B1 mycotoxins. The visual limit of detection for aflatoxin B1 decreased to 0.6ng/mL compared to 11ng/mL with an ordinary test strip. For zearalenone, a test strip was created with visual detection limit of 6ng/mL with reagents inefficient in the traditional test strip (which is not able to detect even 9μg/mL of zearalenone). Thus, the proposed approach allows obtaining 'dry', multi-stage, immunochromatographic test strips, providing a highly sensitive detection method.
在竞争性酶联免疫吸附测定中效果良好的免疫试剂，往往无法在传统的竞争性免疫层析测定中提供所需的检测限。解决方法可能是生产新的试剂或改进测试条。在后一种情况下，通常使用额外的液体试剂分步进行检测，但这对于实际使用来说是一个很大的缺点。我们引入了一种作为干式化学装置的测试条，该测试条仍然提供两步免疫化学反应——特定抗体与抗原形成复合物，以及用抗物种抗体与纳米级标记物的缀合物对其进行检测。使用这种测试条进行分析类似于使用普通测试条，不需要额外的试剂和操作。使用特定的抗体和标记物作为两个单独的组件，可以改善分析参数。新测试条显著降低了检测限，使得以前在免疫层析中无效的抗体得以使用。该方法通过测定玉米赤霉烯酮和黄曲霉毒素 B1 真菌毒素进行了测试。与普通测试条相比，黄曲霉毒素 B1 的视觉检测限降低到 0.6ng/mL，而普通测试条的检测限为 11ng/mL。对于玉米赤霉烯酮，创建了一种具有 6ng/mL 视觉检测限的测试条，使用的试剂在传统测试条中效率低下（甚至无法检测到 9μg/mL 的玉米赤霉烯酮）。因此，所提出的方法允许获得“干式”、多阶段免疫层析测试条，提供一种高灵敏度的检测方法。
