Kamińska Agnieszka, Sprynskyy Myroslav, Winkler Katarzyna, Szymborski Tomasz
Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland.
Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus Copernicus University, 7 Gagarina Str, 87-100, Toruń, Poland.
Anal Bioanal Chem. 2017 Nov;409(27):6337-6347. doi: 10.1007/s00216-017-0566-5. Epub 2017 Aug 29.
An ultrasensitive surface-enhanced Raman scattering (SERS) immunoassay based on diatom biosilica with integrated gold nanoparticles (AuNPs) for the detection of interleukin 8 (IL-8) in blood plasma has been developed. The SERS sensing originates from unique features of the diatom frustules, which are capable of enhancing the localized surface-plasmon resonance of metal nanostructures. The SERS immune tags ware fabricated by functionalizing 70-nm Au nanoparticles with DTNB (i.e., 5,5'-dithiobis(2-nitrobenzoic acid)), which acted as a Raman reporter molecule, as well as the specific antibodies. These DTNB-labeled immune-AuNPs can form a sandwich structure with IL-8 antigens (infection marker) and the antibodies immobilized on the biosilica material. Our method showed an improved IL-8 detection limit in comparison to standard ELISA methods. The current detection limit for IL-8 using a conventional ELISA test is about 15.6 pg mL. The lower detection limit for IL-8 in blood plasma was estimated to be 6.2 pg mL. To the best of our knowledge, this is the first report on the recognition of IL-8 in human samples using a SERS-based method. This method clearly possesses high sensitivity to clinically relevant interleukin concentrations in body fluids. The average relative standard deviation of this method is less than 8%, which is sufficient for analytical analysis and comparable to those of classical ELISA methods. This SERS immunoassay also exhibits high biological specificity for the detection of IL-8 antigens. The established SERS immunoassay offers a valuable platform for the ultrasensitive and highly specific detection of immune biomarkers in a clinical setting for medical diagnostics. Graphical Abstract The SERS-based immunoassay based on naturally generated photonic biosilica for the detection of interleukin 8 (IL-8) in human plasma samples.
一种基于硅藻生物二氧化硅与集成金纳米粒子（AuNPs）的超灵敏表面增强拉曼散射（SERS）免疫分析法已被开发出来，用于检测血浆中的白细胞介素8（IL-8）。SERS传感源于硅藻壳的独特特性，其能够增强金属纳米结构的局域表面等离子体共振。SERS免疫标签是通过用DTNB（即5,5'-二硫代双（2-硝基苯甲酸））对70纳米的金纳米粒子进行功能化制备的，DTNB作为拉曼报告分子以及特异性抗体。这些DTNB标记的免疫AuNPs可以与IL-8抗原（感染标志物）和固定在生物二氧化硅材料上的抗体形成夹心结构。与标准ELISA方法相比，我们的方法显示出改进的IL-8检测限。使用传统ELISA测试检测IL-8的当前检测限约为15.6 pg/mL。血浆中IL-8的较低检测限估计为6.2 pg/mL。据我们所知，这是首次使用基于SERS的方法在人体样本中识别IL-8的报告。该方法对体液中临床相关的白细胞介素浓度显然具有高灵敏度。该方法的平均相对标准偏差小于8%，这足以用于分析分析，并且与经典ELISA方法相当。这种SERS免疫分析法在检测IL-8抗原方面也表现出高生物特异性。所建立的SERS免疫分析法为在临床环境中进行医学诊断时超灵敏和高度特异性地检测免疫生物标志物提供了一个有价值的平台。图形摘要：基于天然生成的光子生物二氧化硅的SERS免疫分析法用于检测人血浆样本中的白细胞介素8（IL-8）。
