Simultaneous absorbance-ratiometric, fluorimetric, and colorimetric analysis and biological imaging of a-ketoglutaric acid based on a special sensing mechanism

• Published in: Sensors and actuators. B, Chemical Chemical, 2017-03, Vol.241, p.1035
• Main Authors: Fu, Qiang, Chen, Zhi, Ma, Xueying, Chen, Guang, Liu, Yuxia, Cao, Ziping, Qu, Fei, Yang, Daoshan, Zhao, Xianen, Sun, Zhiwei, Li, Guoliang, Zhang, Shijuan, Qu, Fengli, Kong, Rongmei, Wang, Hua, You, Jinmao
• Format: Article
• Language: English
• Subjects: Absorption; Biological effects; Biological properties; Biomarkers; Cellular biology; Color sensitivity; Colorimetry; Doppler effect; Electron transfer; Fluorescence; Red shift; Surfactants
• ISSN: 0925-4005; 1873-3077

Probe for α-ketoglutaric acid (α-KA) usually provides low sensitivity, invisible colour change and complex procedure with surfacants, which limits the accurate, sensitive quantification and mornitoring of α-KA in biological samples. Essentially different from the routine sensing mechanism, a special mechanism of photo-induced electron transfer (PET) combining with large absorption red-shift (rather than emission) has been designed to develop a facile yet multifunctional probe for the simultaneous fluorimetric, absorption-ratiometric and colorimetric detections of α-KA in biological samples. Effective inhibition of PET ensured the intense fluorescence turn-on (60 fold) and qutie low detection limit (0.9 μM) for α-KA without need of any surfacants. Dramatical colour change caused by the large absorption red shift (100 nm) from UV–vis region enabled the colormetric analysis of α-KA by naked-eye. Meanwhile, the large absorption red shift also contributed to the ratiometric detection, allowing for the accurate quantification of α-KA in complex biological sample. With this probe, ratiometric detection, naked eye mornitoring and imaging of α-KA in serum, living cells and tissues are realized for the first time.