College of Chemistry and Materials Science, Anhui Key Laboratory of Chemo/Biosensing, The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-based Materials, Anhui Normal University, Wuhu 241000, People's Republic of China.
Nanotechnology. 2021 Aug 13;32(44). doi: 10.1088/1361-6528/ac1978.
Developing ratiometric fluorescence and smartphone dual-mode bioanalysis methods is important but challenging. A ratiometric fluorescence method for determining glutathione (GSH) using carbon dots (CDs) and Ag-triggered o-phenylenediamine (OPD) oxidation is described here. Agoxidizes OPD to give 2,3-diaminophenazine (oxOPD), which effectively quenches CD fluorescence at 436 nm through the inner filter effect and causes a new emission peak at 561 nm. GSH chelates with Agand prevents the Agoxidizing OPD and therefore effectively preserves CD emission at 436 nm (blue) and allows only weak oxOPD fluorescence at 561 nm (orange) to occur. The oxOPD to CD fluorescence intensity ratio decreased linearly as the GSH concentration increased in the range 0-150 nM, and the detection limit was 15 nM. The ratiometric fluorescence probe lit with an ultraviolet lamp clearly changed color from orange to blue as the GSH concentration increased. An image was acquired using a smartphone camera and converted into digital values. The blue and red channel ratio was calculated and used to quantify GSH. The method therefore allows dual-mode detection of GSH.
开发比率荧光和智能手机双模生物分析方法很重要，但具有挑战性。本文描述了一种比率荧光法，用于使用碳点（CDs）和 Ag 触发邻苯二胺（OPD）氧化来测定谷胱甘肽（GSH）。Ag 将 OPD 氧化为 2,3-二氨基吩嗪（oxOPD），通过内滤效应有效猝灭 CD 在 436nm 的荧光，并在 561nm 处产生新的发射峰。GSH 与 Ag 螯合，防止 Ag 氧化 OPD，从而有效地保持 CD 在 436nm（蓝色）处的发射，并且仅允许在 561nm（橙色）处发生弱 oxOPD 荧光。oxOPD 与 CD 荧光强度比随着 GSH 浓度在 0-150nM 范围内的增加而线性降低，检测限为 15nM。用紫外灯照射比率荧光探针时，随着 GSH 浓度的增加，颜色明显从橙色变为蓝色。使用智能手机摄像头获取图像，并将其转换为数字值。计算蓝色和红色通道的比值，并用于定量 GSH。因此，该方法允许对 GSH 进行双模检测。
