Xanthine oxidase (XO) has played a crucial role as one of the key enzymes in the oxidation of purines and the formation of uric acid. Excessive accumulation of uric acid can lead to gout formation and acute gout inflammatory response. Therefore, it has shown significant importance to develop a method for a real-time dynamic detection of XO in vivo, which contributed to the study in purine metabolism, monitoring gout progression and related therapeutic interventions. In this study, a novel near-infrared squaraine fluorescence probe (SQ-T1) was developed for successfully achieving real-time detection of XO in liver cells (LO2) as well as in mice with high sensitivity and specificity. The fluorescence intensity of the probe displayed high correlation with XO activity. All the experimental results indicated that SQ-T1 was a promising real-time fluorescence imaging tool that could be utilized for XO level evaluation in vivo and it could also provide new insights for the development of XO inhibitors and early diagnosis of gout.

中文翻译：

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黄嘌呤氧化酶激活的近红外荧光探针体内成像的开发


黄嘌呤氧化酶（XO）作为嘌呤氧化和尿酸形成的关键酶之一，发挥着至关重要的作用。尿酸过多蓄积可导致痛风形成和急性痛风炎症反应。因此，开发一种实时动态检测体内XO的方法具有重要意义，这有助于嘌呤代谢、监测痛风进展和相关治疗干预的研究。本研究开发了一种新型近红外方酸菁荧光探针（SQ-T1），成功实现了肝细胞（LO2）以及小鼠体内XO的实时检测，具有高灵敏度和特异性。探针的荧光强度与XO活性高度相关。所有实验结果表明，SQ-T1是一种很有前景的实时荧光成像工具，可用于体内XO水平评估，也可为XO抑制剂的开发和痛风的早期诊断提供新的见解。