摘要
A recyclable fluorescence sensor for Hg2+ and Zn2+, based on rhodamine 6G(R6G) and 8-aminoquinoline(8-AQ) co-modified core/shell Fe3O4@Si O2 nanoparticles(denoted as R6G/8-AQ co-functionalized Fe3O4@Si O2 NPs), was developed. R6 G derivative and 8-AQ derivative were conjugated onto the water-soluble core/shell Fe3O4@Si O2 nanoparticles(NPs) by covalent interaction. The R6G/8-AQ co-functionalized core/shell Fe3O4@Si O2 NPs showed fluorescence emission bands at 548 and 480 nm. When the R6G/8-AQ co-functionalized core/shell Fe3O4@Si O2 NPs were coordinated with Hg2+ and Zn2+, emission intensity at 548 nm increased with [Hg2+], while that at 480 nm increased with [Zn2+]. Moreover, there existed approximate linear relationships between fluorescence intensities and concentration of metal ions, in the range of 4.0×10-9–7.65×10-8 M for Hg2+ and 3.3×10-9–3.96×10-8 M for Zn2+, respectively. The lower detection limits for Hg2+ and Zn2+ were 1.0×10-9 and 3.0×10-9 M, respectively. The R6G/8-AQ co-functionalized core/shell Fe3O4@Si O2 NPs showed good selectivity to Hg2+ and Zn2+ over other common metal ions examined in neutral aqueous solutions. Moreover, the R6G/8-AQ co-functionalized core/shell Fe3O4@Si O2 NPs could be recycled from the detected samples using a magnet. This work has thus showed not only a practical sensing method for Zn2+ and Hg2+, but also a promising guide to the design of fluorimetric/colorimetric sensors for other targets.
本文报道了一种荧光分子修饰的亲水性Fe3O4@SiO2核壳纳米颗粒的制备方法,及其对Hg2+和Zn2+的荧光检测.首先,利用溶剂热方法,制备了亲水性的磁性Fe3O4纳米颗粒;然后,利用传统的溶胶凝胶法在Fe3O4纳米颗粒的表面包覆SiO2壳层,得到了Fe3O4@SiO2核壳纳米颗粒;最后,采用共价连接的方式,将8-氨基喹啉(8-AQ)的衍生物(QIOEt)与罗丹明6G(R6G)的衍生物(R6GOEt)修饰到Fe3O4@Si O2核壳纳米颗粒的表面,制备了R6G/8-AQ共同修饰的Fe3O4@SiO2核壳纳米颗粒.研究表明,该双通道荧光纳米颗粒在中性水溶液中对Hg2+和Zn2+有很好的检测选择性和灵敏性,对Zn2+和Hg2+的检测线性范围分别为3.3×10–9~3.96×10–8Μ和4.0×10–9~7.65×10–8Μ.该荧光纳米材料的制备方法简单,对Hg2+和Zn2+的灵敏度高、选择性好,且可重复利用,因此在环境检测领域有广泛的应用前景.
基金
supported by the National Key Basic Research Program of China (2013CB934304)
the National Natural Science Foundation of China (21307138, 11274312, 11175204 and 51472245)
the State Administration of Foreign Experts Affairs of Chinese Academy International Partnership Program for Creative Research Teams, and the President Foundation of Hefei Institutes of Physical Science, Chinese Academy of Sciences (YZJJ201312)
