A novel mitochondrial-targeting near-infrared fluorescent probe for imaging gamma-glutamyl transpeptidase activity in living cells

作者：Liu, Haijuan; Liu, Feng; Wang, Fenglin^*; Yu, Ru-Qin; Jiang, Jian-Hui^*

来源：Analyst, 2018, 143(22): 5530-5535.

DOI：10.1039/c8an01460d

• CANCER
• TRANSFERASE
• AMINOTRANSFERASE
• ALANINE
• THIOLS
• TUMOR

gamma-Glutamyl transpeptidase (GGT) plays an essential role in regulating cellular glutathione and cysteine homeostasis, and its abnormal elevation is associated with different diseases including cancers. Here a novel mitochondrial-targeting near-infrared fluorescent probe was designed for GGT by conjugating glutamate acid to a newly synthesized amine hemicyanine fluorophore. The fluorescent probe was initially non-emissive due to the formation of an amide bond which destroyed the electronic-donating ability of the amine moiety and disrupted the push-pull structure. GGT-mediated cleavage of the gamma-glutamyl bond regenerated the initial fluorophore with distinct intramolecular charge transfer (ICT) and activated the fluorescence signal. The fluorescent probe displayed a linear relationship to the concentration of GGT in the range of 1.0-90 U L-1, with an estimated limit of detection (LOD) of 0.4 U L-1. Its ability to target and image mitochondrial GGT activity was demonstrated in living cells with high specificity and fast response. We believe our near-infrared fluorescent probe could have great potential in imaging mitochondrial GGT activity and elucidating GGT-associated pathological consequences in living cells and even small animal models.

• 出版日期2018-11-21
• 单位化学生物传感与计量学国家重点实验室; 湖南大学