【作者】 夏梦婵； 蔡乐斯； 冯嘉欣； 张四纯； 张新荣；

【Author】 Meng-Chan Xia;Lesi Cai;Jiaxin Feng;Sichun Zhang;Xinrong Zhang;Department of Chemistry, Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Tsinghua University;

【机构】 清华大学化学系；

【摘要】 细胞高度分化且有组织,具有不同酸碱度的各细胞分区间协同作用以维持正常生命活动。pH值异常经常与细胞功能、生长和分化失常相关联,因此,对细胞内pH波动的监测尤为重要。细胞穿膜肽是一类具有穿膜作用的短肽,常常扮演载体的角色载送小分子、多肽、蛋白质、核酸及纳米颗粒进入细胞。我们创新地将细胞穿膜肽融入荧光团中以调节染料的荧光性质,赋予其优异的水溶性、极强的穿膜能力和良好的细胞相容性。据此,我们成功合成了一种新型比率荧光探针,实现了对活细胞内pH变化的灵敏且高度选择性的检测。在pH 3.3-8.1区间内,519 nm和582 nm处荧光信号强度的比值具有56倍的提升。由于该探针在细胞中的广泛分布,不同细胞分区内的pH同时成像得以实现。不同药物刺激细胞后,通过对细胞质和溶酶体pH的同时监测,可以为受激后细胞内H+的重新分布和不同细胞分区间的协同作用提供更加丰富的信息。更多还原

【Abstract】 Cells are highly compartmentalized and organized.Different cellular compartments with varied pH values provide distinct conditions for optimal operation.RhB-R₁₂K-FITC,a new ratiometric fluorescent probe based on cell-penetrating peptides （CPPs） was constructed for pH measurement.Benefiting from the arginine-rich CPP R₁₂K,the fluorescent probe is completely water-soluble,membrane permeable and well biocompatible.It shows high selectivity,sensitivity and reversibility to pH fluctuations.The ratio of fluorescence intensities F₅₁₉/F₅₈₂ increased from 0.2 to 9.2 over the pH range from 3.3 to 8.1.Intracellular pH mapping was successfully realized owing to the wide distribution of the probe in live cells （even in nucleus）.Moreover,cytosolic and lysosomal pH change caused by the stimuli can be simultaneously detected.Compared to other ratiometric pH probes,RhB-R₁₂K-FITC can provide more precise information about H⁺redistribution between different cellular compartments.更多还原