Brennan-Fournet Margaret E, Huerta Miriam, Zhang Yi, Malliaras George, Owens Roisin M
Ecole Nationale Supérieure des Mines, CMP-EMSE, Centre Microélectronique de Provence, 880, route de Mimet, 13541 Gardanne, France.
J Mater Chem B. 2015 Dec 21;3(47):9140-9147. doi: 10.1039/c5tb02060c. Epub 2015 Nov 5.
Protein conformational changes are detected both in vitro and for the first time in the presence of living cells using versatile plasmonic nanoplates. Au-edge-coated triangular silver nanoplates (AuTSNP) exhibit some of the highest refractive index sensitivity values recorded to date and exhibit a strong spectral response to surface biomolecular interactions. Large spectral shifts of over 30 nm distinguish between pH induced compact and extended conformations of the ubiquitous extracellular matrix protein fibronectin (Fn). Conformational transition of Fn from compact to extended is accompanied by a red spectral shift of 27 nm while a corresponding blue spectral shift of 25 nm accompanies the reverse conformational transition. Cleavage of Fn by cathepsin B, which plays an important role in cellular functions and in cancer metastasis is characterised by a blue spectral shift with detection in serum using a straightforward no-wash assay demonstrated. Spectral monitoring of nanoplates decorated with Fn and incubated with MDCK II cells shows extensive shifts of 156 nm and cellular morphological re-arrangement as Fn uncoils from a compact format to from fibrils within the extracellular matrix.
利用多功能等离子体纳米板，在体外以及首次在活细胞存在的情况下检测到了蛋白质构象变化。金边缘包覆的三角形银纳米板（AuTSNP）展现出了一些迄今为止记录到的最高折射率灵敏度值，并且对表面生物分子相互作用表现出强烈的光谱响应。超过30纳米的大幅光谱位移区分了由pH值诱导的普遍存在的细胞外基质蛋白纤连蛋白（Fn）的紧密构象和伸展构象。Fn从紧密构象向伸展构象的转变伴随着27纳米的红移光谱，而反向构象转变则伴随着25纳米相应的蓝移光谱。组织蛋白酶B对Fn的切割在细胞功能和癌症转移中起重要作用，其特征是在血清中检测时出现蓝移光谱，通过一种简单的无需洗涤的检测方法得以证实。对用Fn修饰并与MDCK II细胞一起孵育的纳米板进行光谱监测显示，随着Fn从紧密形式解旋形成细胞外基质中的纤维，出现了156纳米的广泛位移以及细胞形态重排。
