Abstract The development of fluorescent probe(s) for naked eye analyte detection is an emerging area of research. Such probes can be judiciously engineered to realize analyte specific response with high sensitivity and broad applicability. Herein, we report reversible acid-base sensing ability of a donor-acceptor-donor (D-A-D) type thioxanthone-based luminophore 3,6-bis(dimethylamino)-9H-thioxanthen-9-one 10,10-dioxide (3). Photo-physical features of 3 in both the solid and solution states have also been determined. Moreover, the reported probe exhibited aggregation-enhanced emission (AEE) characteristics and pH dependent emission colour. An intramolecular charge transfer (ICT) process was observed between donor (N,N-dimethylamino) and acceptor (thioxanthone) units. The fact that changes can be seen under both the UV and visible lights without any special aid, signifies a remarkable prospect of this organic probe in distinguishing the commonly used laboratory acids of different strength.

中文翻译：

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基于硫杂蒽酮的有机探针具有聚集增强发射和卓越的无机酸传感能力

摘要 用于肉眼分析物检测的荧光探针的开发是一个新兴的研究领域。可以明智地设计此类探针，以实现具有高灵敏度和广泛适用性的分析物特异性响应。在此，我们报告了供体-受体-供体 (DAD) 型基于噻吨酮的发光体 3,6-双(二甲氨基)-9H-噻吨-9-one 10,10-二氧化物 (3) 的可逆酸碱传感能力。3 在固态和溶液状态下的光物理特征也已确定。此外，报道的探针表现出聚集增强发射 (AEE) 特性和 pH 依赖性发射颜色。在供体（N，N-二甲氨基）和受体（噻吨酮）单元之间观察到分子内电荷转移（ICT）过程。