Diabetes Research Group, King's College London School of Medicine, Guy's Hospital, London, SE1 1UL, UK.
Analyst. 2011 Mar 7;136(5):968-72. doi: 10.1039/c0an00430h. Epub 2010 Dec 17.
Alternative, non-electrochemistry-based technologies for continuous glucose monitoring are needed for eventual use in diabetes mellitus. As part of a programme investigating fluorescent glucose sensors, we have developed fibre-optic biosensors using glucose/galactose binding protein (GBP) labelled with the environmentally sensitive fluorophore, Badan. GBP-Badan was attached via an oligohistidine-tag to the surface of Ni-nitrilotriacetic acid (NTA)-functionalized agarose or polystyrene beads. Fluorescence lifetime increased in response to glucose, observed by fluorescence lifetime imaging microscopy of the GBP-Badan-beads. Either GBP-Badan agarose or polystyrene beads were loaded into a porous chamber at the end of a multimode optical fibre. Fluorescence lifetime responses were recorded using pulsed laser excitation, high speed photodiode detection and time-correlated single-photon counting. The maximal response was at 100 mM glucose with an apparent K(d) of 13 mM (agarose) and 20 mM (polystyrene), and good working-day stability was demonstrated. We conclude that fluorescence lifetime fibre-optic glucose sensors based on GBP-Badan are suitable for development as clinical glucose monitors.
需要替代的、基于非电化学的连续血糖监测技术，最终应用于糖尿病领域。作为荧光血糖传感器研究计划的一部分，我们已经开发出了基于纤维光学的生物传感器，该传感器使用葡萄糖/半乳糖结合蛋白（GBP）作为标记物，而 GBP 则标记上了环境敏感荧光团 Badan。通过寡组氨酸标签，将 GBP-Badan 连接到 Ni-亚氨二乙酸（NTA）功能化琼脂糖或聚苯乙烯珠的表面。通过对 GBP-Badan-珠进行荧光寿命成像显微镜观察，发现荧光寿命会对葡萄糖产生响应。将 GBP-Badan 琼脂糖或聚苯乙烯珠装入多模光纤末端的多孔腔室中。使用脉冲激光激发、高速光电二极管检测和时间相关单光子计数来记录荧光寿命响应。在 100mM 葡萄糖下获得最大响应，琼脂糖的表观 K(d)为 13mM，聚苯乙烯的表观 K(d)为 20mM，并且表现出良好的日间工作稳定性。我们得出结论，基于 GBP-Badan 的荧光寿命光纤葡萄糖传感器适合开发为临床血糖监测器。
