title: A novel fluorescent turn-on biosensor based on QDs@GSH-GO fluorescence resonance energy transfer for sensitive glutathione S-transferase sensing and cellular imaging.
abstract: A novel fluorescent turn-on biosensor based on fluorescence resonance energy transfer (FRET) from GSH functionalized Mn-doped ZnS QDs to graphene oxide (GO) was constructed to determine glutathione S-transferases (GSTs) in live cells and human urine. The QDs@GSH is adsorbed on the GO surface via hydrogen bonding interaction between the GSH on the surface of QDs@GSH and GO, and as a result, fluorescence quenching of the QDs@GSH takes place because of FRET. The FRET efficiency from QDs@GSH to GO was calculated to be 86.3%. However, in the presence of GSTs, the FRET process could be inhibited by the specific interaction between the GSH on the surface of QDs@GSH and GSTs, which would keep the QDs@GSH far away from the GO surface, leading to the recovery of the fluorescence. The proposed sensor exhibited high sensitivity, selectivity, and excellent specificity in the buffer, live cells and human urine for the detection of GSTs. Under the physiological conditions (pH 7.4), dissociation constants and the detection limit of GST and ATP6 V1F (a GST-tagged protein) were estimated to be 8.0 × 10-9M, 2.1 × 10-10M and 3.5 × 10-9M, 7.2 × 10-11M, respectively. The presented method has been successfully utilized for the determination of the GSTs in live cells and human urine without any complicated pretreatment and the recovery was in the range of 80%-90%.
authors.affiliation: Research Center for Analytical Sciences, College of Chemistry, Tianjin Key Laboratory of Biosensing and Molecular Recognition, State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin 300071, China. lxchen@nankai.edu.cn.
authors.forename: Lifang
authors.initials: L
authors.lastname: Chang
authors.affiliation: Research Center for Analytical Sciences, College of Chemistry, Tianjin Key Laboratory of Biosensing and Molecular Recognition, State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin 300071, China. lxchen@nankai.edu.cn.
authors.forename: Xiwen
authors.initials: X
authors.lastname: He
authors.affiliation: Research Center for Analytical Sciences, College of Chemistry, Tianjin Key Laboratory of Biosensing and Molecular Recognition, State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin 300071, China. lxchen@nankai.edu.cn and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300071, China.
authors.forename: Langxing
authors.identifier: http://orcid.org/0000-0002-8616-9207
authors.initials: L
authors.lastname: Chen
authors.affiliation: Research Center for Analytical Sciences, College of Chemistry, Tianjin Key Laboratory of Biosensing and Molecular Recognition, State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin 300071, China. lxchen@nankai.edu.cn and Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
authors.forename: Yukui
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000818:Animals; D015374:Biosensing Techniques; D002460:Cell Line; D031541:Fluorescence Resonance Energy Transfer; D005982:Glutathione Transferase / Q000032:analysis* / Q000652:urine; D006108:Graphite; D006801:Humans; D051379:Mice; D045663:Quantum Dots; D012680:Sensitivity and Specificity
chemical_list: D006108:Graphite; D005982:Glutathione Transferase