Intragastric pH acts an important role in the disintegration of food and therapeutic drugs. The generation of some gastric diseases, such as gastric ulcer, gastritis or gastric cancer, may affect the normal secretion of gastric acid, causing abnormal pH in the stomach. Thus, monitoring the pH-fluctuations in stomach could aid the diagnosis of several gastric diseases and in understanding therapeutic effect. Herein, we developed a near-infrared (NIR) fluorescent probe (Cyp) for the real-time and in-situ imaging pH changes in vitro and in vivo. The probe was designed by integrating dimethylamine moiety into cyanine (Cy7) and displayed an increasing NIR emission with pKa values of ca. 4.38 in PBS buffer from pH 2.0 and 7.0. Moreover, the robust probe can detect the pH fluctuations in the living cells during autophagy and drug stimulation. Importantly, the unique probe Cyp could dynamically and real-time in situ image the pH fluctuations in gastrointestinal caused by anti-acid medicine with deep penetration. As a typical gastric disease, gastric ulcer was successfully diagnosed by using the powerful pH probe, for the first time. Both the in vitro and in vivo experiments show that the robust probe has a potential application in imaging-guided gastric diseases diagnostics and therapeutics.

胃内 pH 在食物和治疗药物的分解中起着重要作用。一些胃病的发生，如胃溃疡、胃炎或胃癌等，可能会影响胃酸的正常分泌，导致胃内酸碱度异常。因此，监测胃中的 pH 值波动可以帮助诊断多种胃病并了解治疗效果。在此，我们开发了一种近红外 (NIR) 荧光探针 ( Cyp )，用于在体外和体内实时和原位成像 pH 值变化。该探针是通过将二甲胺部分整合到花青 (Cy7) 中而设计的，并显示出增加的 NIR 发射，pKa 值为约。4.38 在 pH 2.0 和 7.0 的 PBS 缓冲液中。此外，坚固的探针可以检测自噬和药物刺激过程中活细胞的 pH 值波动。重要的是，独特的探针Cyp可以动态、实时地原位成像抗酸药引起的胃肠道pH值波动，具有深度渗透性。胃溃疡作为一种典型的胃病，首次使用功能强大的pH探针成功诊断。无论是在体外和体内实验表明，健壮探针具有在成像引导胃疾病的诊断和治疗具有潜在的应用。