Pentaethylenehexamine and d-penicillamine co-functionalized graphene quantum dots for fluorescent detection of mercury(II) and glutathione and bioimaging

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Vol. 203; pp. 139 - 146
• Main Authors: Ping, Yan, Ruiyi, Li, Yongqiang, Yang, Zaijun, Li, Zhiguo, Gu, Guangli, Wang, Junkang, Liu
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 05.10.2018
• Subjects: Fluorescence probe; Glutathione; Hg2; Sequential recognition; SW480 cell; Hg2; Fluorescence probe; Sequential recognition; Glutathione; SW480 cell; Hg(2+)
• ISSN: 1386-1425; 1873-3557
• DOI: 10.1016/j.saa.2018.05.118

Pentaethylenehexamine and d-penicillamine co-functionalized graphene quantum dots (PEHA-GQD-DPA) was made via one two-step thermal pyrolysis. The resulting PEHA-GQD-DPA is composed of the graphene sheets with an average size of 3.16 nm and the rich of functional groups. It gives an ultra strong fluorescence emission with the fluorescent quantum yield of 90.91% and sensitive and selective optical response towards Hg2+. The fluorescence intensity linearly decreases with the increase of Hg2+ in the range of 1.0 × 10−10–2 × 10−4 M with the detection limit of 4.6 × 10−11 M (S/N = 3). No species tested interfere with detection of Hg2+. The fluorescence quenched by Hg2+ can be well recovered by glutathione. The fluorescence intensity linearly increases with the increase of glutathione in the range of 5 × 10−8–2.5 × 10−6 M with the detection limit of 1.7 × 10−8 M (S/N = 3). The PEHA-GQD-DPA as a fluorescence probe has been successfully applied in determination of Hg2+ in natural water and glutathione in human serum and SW480 cell imaging. The paper reports synthesis of pentaethylenehexamine and d-penicillamine co-functionalized graphene quantum dots. The unique structure achieves to excellent optical behaviors of graphene quantum dots. The fluorescence probe has been successfully used for sequential detection of Hg2+, glutathione and bioimaging. [Display omitted] •We report pentaethylenehexamine and d-penicillamine functionalized graphene quantum dots.•The functionalized graphene quantum dots offers ultra strong fluorescence emission.•The unique structure of graphene quantum dots achieves to excellent optical properties.•The sensor was successfully used for sequential detection of Hg2+, glutathione and bioimaging.