Abstract It is significant for cell physiology to keep the homeostasis of pH, and it is highly demanded to develop ratiometric fluorescent sensors toward pH. In this work, under mild condition, through the electrostatic interaction between carbon nanodots (CDs) and organic molecules, two novel ratiometric fluorescence hybrid nanosensors were fabricated for sensing acidic pH. These nanohybrid systems possess dual emission peaks at 455 and 527 nm under a single excitation wavelength of 380 nm in acidic pH condition. With the increasing of pH, the fluorescence of the 1,8-naphthalimide derivative completely quenches, while the blue fluorescence of CDs keeps constant. Furthermore, the CDs−organic molecular nanohybrids exhibit excellent anti-disturbance ability, reversible pH sensing ability, and a linear response range in wide pH range respectively. Besides the ability to target lysosome, with one of the nanosensor, stimulated pH change has been successfully tracked in a ratiometric manner via fluorescence imaging.

中文翻译：

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碳纳米点的比例荧光检测溶酶体中的酸性pH

摘要保持pH的动态平衡对细胞生理学具有重要意义，因此迫切需要开发出面向pH的比例荧光传感器。在这项工作中，在温和的条件下，通过碳纳米点（CD）与有机分子之间的静电相互作用，制造了两种新颖的比率式荧光杂化纳米传感器，用于感测酸性pH。这些纳米杂化系统在酸性pH条件下，在380 nm的单个激发波长下，在455和527 nm处具有双发射峰。随着pH值的增加，1,8-萘二甲酰亚胺衍生物的荧光完全猝灭，而CD的蓝色荧光保持恒定。此外，CDs-有机分子纳米杂化物在宽的pH范围内分别具有出色的抗干扰能力，可逆的pH传感能力和线性响应范围。