Rapid, quantitative colorimetric detection of a lectin using mannose-stabilized gold nanoparticles
Rapid, quantitative colorimetric detection of a lectin using mannose-stabilized gold nanoparticles
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DOI：
10.1021/la034358v
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发表时间：
2003-08-19
期刊：
影响因子：
3.9
通讯作者：
Russell, DA
中科院分区：
文献类型：
--
作者：
Hone, DC;Haines, AH;Russell, DA
涉及碳水化合物的分子识别事件发生在多种重要的生物过程中，包括免疫系统的功能、病毒和细菌的相互作用1以及组织生长。 2 这些现象涉及细胞间通讯事件，这些通讯事件是由相对细胞表面上高度特异性的碳水化合物凝集素相互作用驱动的。 3 参与这些分子识别过程的蛋白质通常存在于聚集结构中，从而为碳水化合物配体提供多个结合或识别位点。这种聚集结构增强了单体糖蛋白相互作用的低结合亲和力，这种观察被称为簇糖苷效应。 4 考虑到这种相互作用的重要性，大量的研究工作集中在开发新方法来研究和量化这些分子识别事件，特别关注多价碳水化合物配体的形成。此前，碳水化合物结构已被公式化：作为 2D 表面上的自组装单层 (SAM)，作为单个配体 5-7 以及最近在阵列中； 8-11作为树枝状聚合物； 12在脂质体内； 13 以及聚合物的主链。 14 最近，金属纳米粒子已被用来束缚各种碳水化合物配体。 15-18 这种 3D 多价配体提供了球状结构，可以研究其聚类和取向效应。 16 此外，金属核的特性可用于开发研究碳水化合物及其各自结合蛋白之间分子识别的方法。例如，甘露糖稳定的金纳米粒子已被用于通过电子显微镜观察大肠杆菌 1 型菌毛上的 FimH 蛋白。 17 可以使用的其他固有特性基于金属纳米粒子的光学特性，这些特性主要由相互作用的电磁场引起的导带电子的相干振荡支配。 19 这种光吸收称为表面等离子体吸收，取决于金属的介电特性、颗粒的大小和形状以及周围的介质。金纳米颗粒通常具有以 520 nm 为中心的大表面等离子体吸收带，因此金纳米颗粒的水溶液呈现红色。聚集后，金属颗粒变得更加接近，耦合相互作用导致表面等离子体吸收转变为较低能量。 Mirkin 及其同事利用这一概念开发了一种用于 DNA 分析的比色测定法。 20, 21 随后，这种方法被用于检测金属离子，22, 23 充分研究的生物素-亲和素相互作用，24 以及抗体免疫测定。 25 此外，Kataoka 和同事还自组装了聚（乙二醇）衍生碳水化合物，用于比色检测 Recinus communis 凝集素 (RCA120)。 18此处报道了用于碳水化合物结合蛋白比色检测的稳定胶体系统的进一步开发。甘露糖衍生物已自组装到预成型的柠檬酸盐封端的水溶性金纳米颗粒上。通过在金表面和甘露糖识别中心之间使用短 (C2) 烃系链，针对碳水化合物结合蛋白伴刀豆球蛋白 A 开发了一种选择性、定量且重要的是快速比色检测方法。
Molecular recognition events involving carbohydrates occur in a wide variety of important biological processes including the functioning of the immune system, interaction of viruses and bacteria, 1 and tissue growth. 2 Involved in these phenomena are cell-cell communication events, which are driven by highly specific carbohydratelectin interactions on opposing cell surfaces. 3 The proteins involved in these molecular recognition processes are typically found in aggregated structures thereby presenting multiple binding or recognition sites for the carbohydrate ligand. Such aggregated structures enhance the low binding affinity of the monomeric carbohydrateprotein interaction, an observation referred to as the cluster glycoside effect. 4 With consideration of the importance of such interactions, considerable research effort has focused on the development of new methodologies to study and quantify these molecular recognition events with particular attention on the formation of multivalent carbohydrate ligands. Previously, carbohydrate structures have been formulated: as self-assembled monolayers (SAMs) on 2D surfaces, both as single ligands5-7 and more recently within arrays; 8-11 as dendrimers; 12 within liposomes; 13 and on the backbone of polymers. 14 Recently, metal nanoparticles have been used to tether a variety of carbohydrate ligands. 15-18 Such 3D multivalent ligands provide a globular structure on which clustering and orientation effects may be studied. 16 In addition, the properties of the metal core can be applied to develop methods for the study of molecular recognition between carbohydrates and their respective binding proteins. For example, mannose-stabilized gold nanoparticles have been used to visualize FimH proteins on type 1 pili of Escherichia coli using electron microscopy. 17 Other inherent properties which can be used are based on the optical characteristics of metal nanoparticles which are dominated by the coherent oscillations of the conduction band electrons induced by an interacting electromagnetic field. 19 This absorption of light is known as surface plasmon absorption and is dependent on the dielectric properties of the metal, the size and shape of the particles, and the surrounding medium. Gold nanoparticles typically have a large surface plasmon absorption band centered at 520 nm, and thus aqueous solutions of gold nanoparticles appear red. Upon aggregation, the metal particles become closer in proximity and coupling interactions result in a shift in the surface plasmon absorption to lower energies. This concept has been utilized by Mirkin and co-workers to produce a colorimetric assay for the analysis of DNA. 20, 21 Subsequently this approach has been adopted for the detection of metal ions, 22, 23 the well-studied biotin-avidin interaction, 24 and for antibody immunoassays. 25 Additionally, Kataoka and co-workers have self-assembled poly-(ethylene glycol)-derivatized carbohydrates for the colorimetric detection of Recinus communis agglutinin (RCA120). 18Here the further development of stabilized colloidal systems for the colorimetric detection of carbohydrate binding proteins is reported. A mannose derivative has been self-assembled onto preformed, citrate capped, watersoluble gold nanoparticles. Through the use of a short (C2) hydrocarbon tether between the gold surface and the mannose recognition center, a selective, quantitative, and, importantly, rapid colorimetric detection method has been developed for the carbohydrate binding protein concanavalin A.