title: Fluorescence analysis of 6-mercaptopurine with the use of a nano-composite consisting of BSA-capped Au nano-clusters and core-shell Fe3O4-SiO2 nanoparticles.
abstract: A magnetic and fluorescent nano-composite was prepared. It comprised of a core of Fe3O4 nanoparticles (NPs), a silica shell and satellitic Au nano-clusters (AuNCs) capped with bovine serum albumin (BSA). This nano-composite has many desirable properties, e.g. magnetism, red emission, high water solubility, and high resistance to photo-bleaching. On addition of the analyte, 6-mercaptopurine (6-MP) or indeed other similar thiols, AuNCs formed aggregates because the existing cross-links within the Fe3O4 NPs@SiO2 and AuNC structure were broken in favor of the gold-thiol bonds. On suitable irradiation of such aggregates, red fluorescence was emitted at 613 nm. It decreased significantly as a function of the added 6-MP concentration, and the quenching ratio (F0 - F) / F0 was related linearly to the concentration of 6-MP in the range of 0.01 to 0.5 μmol L(-1). The detection limit was 0.004 μmol L(-1) (S/N=3). The method was strongly selective for 6-MP in the presence of oxidants, phenols, heavy-metal ions, and especially bio-thiols.
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China; Department of Chemistry, Nanchang University, Nanchang 330031, China.
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Chemistry, Nanchang University, Nanchang 330031, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China; Department of Chemistry, Nanchang University, Nanchang 330031, China. Electronic address: ynni@ncu.edu.cn.
authors.forename: Yongnian
authors.initials: Y
authors.lastname: Ni
authors.affiliation: School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology, Brisbane 4001, Australia. Electronic address: s.kokot@qut.edu.au.
authors.forename: Serge
authors.initials: S
authors.lastname: Kokot
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000032:analysis; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis; D006046:Gold / Q000737:chemistry; D058185:Magnetite Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D015122:Mercaptopurine / Q000032:analysis* / Q000737:chemistry; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D058608:Nanopores / Q000648:ultrastructure; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods*
chemical_list: D000964:Antimetabolites, Antineoplastic; D020099:Coated Materials, Biocompatible; D058185:Magnetite Nanoparticles; D012710:Serum Albumin, Bovine; D006046:Gold; D012822:Silicon Dioxide; D015122:Mercaptopurine
keywords: 6-mercaptopurine; Au nano-clusters; Fe(3)O(4) nanoparticles; Fluorescence analysis