College of Chemistry, Chemical Engineering and Materials Science, Shandong Provincial Engineering and Technical Center of Light Manipulations, Shandong Provincial Key Laboratory of Optics and Photonic Device, School of Physics and Electronics, Shandong Normal University, Ji'nan, 250014, China.
College of Chemistry, Chemical Engineering and Materials Science, Shandong Provincial Engineering and Technical Center of Light Manipulations, Shandong Provincial Key Laboratory of Optics and Photonic Device, School of Physics and Electronics, Shandong Normal University, Ji'nan, 250014, China.
Anal Chim Acta. 2024 Aug 1;1315:342825. doi: 10.1016/j.aca.2024.342825. Epub 2024 Jun 4.
Non-invasive indirect blood glucose monitoring can be realized by detecting low concentrations of glucose (0.05-5 mM) in tears, but sensitive optical indicators are required. The intensity of the phosphorescence of a candidate optical indicator, palladium hematoporphyrin monomethyl ether (Pd-HMME), is increased by oxygen consumption under sealed conditions in the presence of glucose and glucose oxidase. However, the glucose detection limit based on this mechanism is high (800 μM) because the phosphorescence is completely quenched under ambient oxygen conditions and hence a large amount of glucose is required to reduce the oxygen levels such that the phosphorescence signal is detectable.
To improve the glucose detection limit of Pd-HMME phosphorescence-based methods, the triplet protector imidazole was introduced, and strong phosphorescence was observed under ambient oxygen conditions. Detectable phosphorescence enhancement occurred at low glucose concentrations (<200 μM). Linear correlation between the phosphorescence intensity and glucose concentration was observed in the range of 30-727 μM (R = 99.9 %), and the detection limit was ∼10 μM. The glucose sensor has a fast response time (∼90 s) and excellent selectivity for glucose.
These results indicate the potential of the developed optical indicator for fast, selective, and reliable low-concentration glucose sensing.
通过检测泪液中低浓度的葡萄糖（0.05-5mM），可以实现非侵入性间接血糖监测，但需要敏感的光学指示剂。在存在葡萄糖和葡萄糖氧化酶的密封条件下，候选光学指示剂钯血卟啉单甲醚（Pd-HMME）的磷光强度会因消耗氧气而增加。然而，基于这种机制的葡萄糖检测限较高（800μM），因为在环境氧气条件下磷光会完全猝灭，因此需要大量的葡萄糖来降低氧气水平，以使磷光信号可检测。
为了提高 Pd-HMME 磷光法的葡萄糖检测限，引入了三重态保护剂咪唑，在环境氧气条件下观察到强磷光。在低葡萄糖浓度（<200μM）下观察到可检测的磷光增强。在 30-727μM 范围内观察到磷光强度与葡萄糖浓度之间的线性相关性（R=99.9%），检测限约为 10μM。该葡萄糖传感器具有快速的响应时间（~90s）和对葡萄糖的优异选择性。
这些结果表明，所开发的光学指示剂具有用于快速、选择性和可靠的低浓度葡萄糖感测的潜力。
