title: Microwave assisted one-pot synthesis of graphene quantum dots as highly sensitive fluorescent probes for detection of iron ions and pH value.
abstract: Recently, carbon nanomaterials have received considerable attention as fluorescent probes owing to their low toxicity, water solubility and stable photochemical properties. However, the development of graphene quantum dots (GQDs) is still on its early stage. In this work, GQDs were successfully synthesized by one-step microwave assisted pyrolysis of aspartic acid (Asp) and NH4HCO3 mixture. The as-prepared GQDs exhibited strongly blue fluorescence with high quantum yield up to 14%. Strong fluorescence quenching effect of Fe(3+) on GQDs can be used for its high selectivity detection among of general metal ions. The probe exhibited a wide linear response concentration range (0-50 μM) to Fe(3+) and the limit of detection (LOD) was calculated to be 0.26 μM. In addition, GQDs are also sensitive to the pH value in the range from 2 to 12 indicating a great potential as optical pH sensors. More importantly, the GQDs possess lower cellular toxicity and high photostability and can be directly used as fluorescent probes for cell imaging.
authors.affiliation: College of Materials Science and Opto-electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Chunfang
authors.initials: C
authors.lastname: Zhang
authors.affiliation: College of Materials Science and Opto-electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Cui
authors.affiliation: College of Materials Science and Opto-electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Li
authors.initials: L
authors.lastname: Song
authors.affiliation: College of Materials Science and Opto-electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: liuxf@ucas.ac.cn.
authors.forename: Xiangfeng
authors.initials: X
authors.lastname: Liu
authors.affiliation: College of Materials Science and Opto-electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: huzq@ucas.ac.cn.
authors.forename: Zhongbo
authors.initials: Z
authors.lastname: Hu
mesh_terms: D045744:Cell Line, Tumor; D060326:Chemistry Techniques, Synthetic; D005240:Feasibility Studies; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000032:analysis* / Q000737:chemistry*; D057230:Limit of Detection; D008872:Microwaves; D057054:Molecular Imaging; D045663:Quantum Dots / Q000737:chemistry*; D013050:Spectrometry, Fluorescence
chemical_list: D005456:Fluorescent Dyes; D006108:Graphite; D007501:Iron
keywords: Bioimaging; Detection of Fe(3+); Fluorescence; Graphene quantum dots; Sensor