Near-infrared fluorescence glucose sensing based on glucose/galactose-binding protein coupled to 651-Blue Oxazine
Near-infrared fluorescence glucose sensing based on glucose/galactose-binding protein coupled to 651-Blue Oxazine
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DOI：
10.1016/j.bbrc.2013.07.111
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发表时间：
2013-08-30
影响因子：
3.1
通讯作者：
Pickup, John C.
中科院分区：
文献类型：
--
作者：
Khan, Faaizah;Pickup, John C.
环境敏感或溶剂化显色的近红外 (NIR) 荧光染料是体内生物传感器应用中蛋白质标记的有用工具，例如糖尿病中的葡萄糖监测，因为它们的光谱特性大多独立于组织自发荧光和光散射，并且它们提供了非侵入性分析物传感的潜力。我们发现荧光团 651-Blue Oxazine 对极性敏感，随着溶剂极性的增加，NIR 荧光显着降低。使用点击化学，用蓝色恶嗪对用作葡萄糖受体的葡萄糖/半乳糖结合蛋白（GBP）突变体进行位点特异性共价标记。突变体 H152C/A213R 和 H152C/A213R/L238S 在添加饱和葡萄糖浓度以及 6 和 25 mM 的结合常数时分别显示荧光增加 15% 和 21%。当 GBP-Blue 恶嗪固定在琼脂糖珠上时，对葡萄糖的荧光反应得以保留，并且珠子通过体外研究的小鼠皮肤制剂被近红外光激发。我们得出结论，GBP-Blue Oxazine 显示了作为非侵入性连续葡萄糖传感系统的概念验证。 (C) 2013 Elsevier Inc. 保留所有权利。
Near-infrared (NIR) fluorescent dyes that are environmentally sensitive or solvatochromic are useful tools for protein labelling in in vivo biosensor applications such as glucose monitoring in diabetes since their spectral properties are mostly independent of tissue autofluorescence and light scattering, and they offer potential for non-invasive analyte sensing. We showed that the fluorophore 651-Blue Oxazine is polarity-sensitive, with a marked reduction in NIR fluorescence on increasing solvent polarity. Mutants of glucose/galactose-binding protein (GBP) used as the glucose receptor were site-specifically and covalently labelled with Blue Oxazine using click chemistry. Mutants H152C/A213R and H152C/A213R/L238S showed fluorescence increases of 15% and 21% on addition of saturating glucose concentrations and binding constants of 6 and 25 mM respectively. Fluorescence responses to glucose were preserved when GBP-Blue Oxazine was immobilised to agarose beads, and the beads were excited by NIR light through a mouse skin preparation studied in vitro. We conclude GBP-Blue Oxazine shows proof-of-concept as a non-invasive continuous glucose sensing system. (C) 2013 Elsevier Inc. All rights reserved.