Guangxi Key Laboratory of Electrochemical Energy Materials, Institute of Optical Materials and Chemical Biology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning, Guangxi 530004, P. R. China.
J Mater Chem B. 2021 Oct 20;9(40):8417-8423. doi: 10.1039/d1tb01509e.
Chymotrypsin (CHT) plays a vital role in the metabolism of organisms and affects cell proliferation and apoptosis. Abnormal levels of CHT will lead to a variety of diseases, such as inflammatory arthritis, diabetes, pharyngitis, indigestion, and pancreatic cancer. Therefore, it is significant to design an effective method for the detection of CHT in living systems. Here, we synthesized a specific deep-red non-peptide probe DT by effectively combining isophorone and -hydroxybenzaldehyde for the detection of CHT using 3-phenylpropionate chloride as the recognition group based on a protection-deprotection strategy. The DT probe exhibited an emission range of 525-700 nm and showed excellent photostability, high sensitivity (LOD = 0.071 U mL), and selectivity for CHT detection. The cellular experiments demonstrated that DT could sensitively recognize CHT activity in three cell lines and the content of CHT was much higher in P815 cells than in MCF-7 and 3T3 cells. Also, DT was successfully used to visualize the endogenous CHT in zebrafish. Notably, the DT probe provided an intuitive way to visualize endogenous CHT in mouse pancreas for the first time, demonstrating the potential for application in the future clinical diagnosis of pancreatic diseases. Therefore, the small-molecule probe DT is expected to be a useful molecular tool for CHT-related disease diagnosis and drug discovery.
糜蛋白酶（CHT）在生物体的代谢中起着至关重要的作用，影响细胞增殖和凋亡。CHT 水平异常会导致多种疾病，如炎症性关节炎、糖尿病、咽炎、消化不良和胰腺癌。因此，设计一种在活系统中有效检测 CHT 的方法具有重要意义。在这里，我们通过将异佛尔酮和 -羟基苯甲醛有效结合，并基于保护-脱保护策略，使用 3-苯丙酸氯作为识别基团，合成了一种特异性的深红光非肽探针 DT，用于检测 CHT。DT 探针的发射范围为 525-700nm，表现出优异的光稳定性、高灵敏度（LOD=0.071UmL）和对 CHT 检测的选择性。细胞实验表明，DT 可以敏感地识别三种细胞系中的 CHT 活性，并且 P815 细胞中的 CHT 含量明显高于 MCF-7 和 3T3 细胞。此外，DT 成功地用于可视化斑马鱼内源性 CHT。值得注意的是，DT 探针首次提供了一种直观的方法来可视化小鼠胰腺中的内源性 CHT，为未来胰腺疾病的临床诊断应用提供了潜力。因此，小分子探针 DT 有望成为与 CHT 相关疾病诊断和药物发现的有用分子工具。
