Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education), College of Chemistry and Chemical Engineering, Guangxi Normal University, Guilin, 541004, China.
Luminescence. 2013 Sep-Oct;28(5):662-6. doi: 10.1002/bio.2412. Epub 2012 Sep 4.
Water-soluble graphene oxide (GO) with a two-dimensional layered nanostructure was synthesized and used as a quencher to construct a highly sensitive and selective fluorescence resonance energy transfer (FRET) aptasensor for sensing Immunoglobulin E (IgE). The fluorescein isothiocyanate (FITC)-labeled aptamer could be adsorbed stably onto the surface of GO via π → π stacking interaction, which led to the occurrence of FRET from FITC to GO, and the fluorescence of FITC-labeled aptamer was quenched by GO via energy transfer. In the presence of IgE, the fluorescence was recovered due to a higher affinity between the aptamer and IgE compared with interactions between GO and the aptamer, leading to a high signal-to-background ratio. The fluorescence intensity of the aptamer increased in proportion to the amount of IgE in the sample,so that IgE could be detected with a linear range of 60-225 pM and a detection limit of 22 pM. The assay was highly selective because the aptamer was unaffected by the presence of immunoglobulin G (IgG), human serum albumin (HSA) and bovine serum albumin (BSA). The practical application of the proposed aptasensor was successfully carried out for the determination of IgE in human serum samples.
合成了具有二维层状纳米结构的水溶性氧化石墨烯（GO），并将其用作猝灭剂，构建了一种用于检测免疫球蛋白 E（IgE）的高灵敏度和选择性的荧光共振能量转移（FRET）适体传感器。通过π-π堆积相互作用，异硫氰酸荧光素（FITC）标记的适体可以稳定地吸附在 GO 的表面上，这导致FRET 从 FITC 到 GO 的发生，并且 GO 通过能量转移使 FITC 标记的适体的荧光猝灭。在 IgE 的存在下，由于适体与 IgE 之间的亲和力高于 GO 与适体之间的相互作用，荧光得到恢复，从而产生高的信号背景比。由于适体与 IgE 之间的亲和力高于适体与 GO 之间的相互作用，因此荧光强度与样品中 IgE 的量成正比，从而可以检测到 IgE 的线性范围为 60-225 pM，检测限为 22 pM。由于适体不受免疫球蛋白 G（IgG）、人血清白蛋白（HSA）和牛血清白蛋白（BSA）的存在的影响，因此该测定法具有高度的选择性。该传感器已成功用于测定人血清样品中的 IgE。
