title: Organic liquids-responsive β-cyclodextrin-functionalized graphene-based fluorescence probe: label-free selective detection of tetrahydrofuran.
abstract: In this study, a label-free graphene-based fluorescence probe used for detection of volatile organic liquids was fabricated by a simple, efficient and low-cost method. To fabricate the probe, a bio-based β-cyclodextrin (β-CD) was firstly grafted on reduced graphene surfaces effectively and uniformly, as evidenced by various characterization techniques such as Ultraviolet/Visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, scanning electron microscopy and transmission electron microscopy. The subsequent inclusion of Rhodamine B (RhB) into the inner cavities of the β-CD grafted on the graphene surfaces was achieved easily by a solution mixing method, which yielded the graphene-based fluorescent switch-on probe. In addition, the gradual and controllable quenching of RhB by Fluorescence Resonance Energy Transfer from RhB to graphene during the process of stepwise accommodation of the RhB molecules into the β-CD-functionalized graphene was investigated in depth. A wide range of organic solvents was examined using the as-fabricated fluorescence probe, which revealed the highest sensitivity to tetrahydrofuran with the detection limit of about 1.7 μg/mL. Some insight into the mechanism of the different responsive behaviors of the fluorescence sensor to the examined targets was also described.
authors.affiliation: The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China. hua.w.hu@connect.polyu.hk.
authors.forename: Huawen
authors.initials: H
authors.lastname: Hu
authors.affiliation: The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China. tcxinjh@polyu.edu.hk.
authors.forename: John H
authors.initials: JH
authors.lastname: Xin
authors.affiliation: The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China. tchuhong@polyu.edu.hk.
authors.forename: Hong
authors.initials: H
authors.lastname: Hu
authors.affiliation: The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China. wang.xiaowen@polyu.edu.hk.
authors.forename: Xiaowen
authors.initials: X
authors.lastname: Wang
authors.affiliation: The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China. xk.lu@polyu.edu.hk.
authors.forename: Xinkun
authors.initials: X
authors.lastname: Lu
mesh_terms: D005453:Fluorescence; D031541:Fluorescence Resonance Energy Transfer; D005663:Furans / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D012235:Rhodamines / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction; D047392:beta-Cyclodextrins / Q000737:chemistry*
chemical_list: D005663:Furans; D012235:Rhodamines; D047392:beta-Cyclodextrins; C018674:tetrahydrofuran; D006108:Graphite; C029773:rhodamine B