Visualization of the pH-fluctuations in gastric ulcer living mice by the in situ near-infrared imaging

• Published in: Sensors and actuators. B, Chemical Vol. 349; p. 130747
• Main Authors: Ma, Yanyan, Liu, Yongyuan, Jiang, Zike, Lv, Hongmin, Wang, Jing, Wang, Tao, Zhang, Xiaonan, Hu, Yimeng, Lin, Haitao, Lin, Weiying
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 15.12.2021; Elsevier Science Ltd
• Subjects: Disintegration; Fluorescent indicators; Fluorescent probe; Gastric ulcer; In vitro and in vivo; Infrared imaging; Intragastric acidity; Medical imaging; Near infrared radiation; pH, near-infrared; Real time; Robustness; Stomach; Ulcers; pH, near-infrared; In vitro and in vivo; Gastric ulcer; Intragastric acidity; Fluorescent probe
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2021.130747

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. [Display omitted] A near-infrared fluorescent probe for sensing the changes of pH in vitro and in vivo was synthesized. With the robust probe, we successfully visualized the pH fluctuations in the living cells during autophagy, drug stimulation. Cyp is able to dynamically and in situ detect intragastric pH variations in living mice during the acid suppression therapy, for the first time. Notably, the unique probe can be efficaciously applied for the diagnosis of gastric injury for the first time by using in vivo imaging technology. •We have developed a NIR fluorescent probe (Cyp) for real-time in situ monitoring pH fluctuation in living system.•The unique probe Cyp displayed a large turn-on signal in PBS buffer from pH 2.0 and 7.0 with NIR emission.•The Cyp was successfully used to image the pH changes in living cells during autophagy and drug stimulation.•The gastrointestinal acidity during an acid suppression therapy can be imaged in real-time by using probe Cyp.•The probe Cyp was used for in situ monitoring the pH fluctuations in gastric ulcer mice, for the first time.