A ratiometric fluorescence method is designed and exploited for the sensitive detection of Hg2+ and Fe3+ ions, which is prepared by simply mixing bovine serum albumin-protected gold/silver nanoclusters (BSA-Au/Ag NCs) with histidine-stabilized gold nanoclusters (His-Au NCs). The as-prepared Au NCs/Au-Ag NCs solution emits pink fluorescence and exhibits two emission peaks around 485 and 660 nm excited by 370 nm. The fluorescence of the Au NCs/Au-Ag NCs system at 660 nm is obviously quenched in the presence of Hg2+, while the fluorescence at 485 nm is stable against Hg2+, thereby resulting in the decrease of fluorescence intensity ratio (I660/I485) of the system. The detection limit for Hg2+ is low as 1.56 nM. With the addition of Fe3+, the dual emission peaks of the Au NCs/Au-Ag NCs in the system show a substantial decline simultaneously with different rate, leading to the Fe3+ ions concentration-dependent variation of I660/I485 value. The linear detection range for Fe3+ is from 5 to 1000 μM. Furthermore, the developed fluorimetric strategy has been employed for separately analysis of different ions Hg2+ and Fe3+ in fish samples with satisfactory results.

中文翻译：

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基于BSA保护的Au / Ag纳米团簇和His稳定的Au纳米团簇的Hg2 +和Fe3 +的比例荧光检测。

设计并开发了一种比率荧光方法，用于灵敏检测Hg2 +和Fe3 +离子，该方法只需将牛血清白蛋白保护的金/银纳米簇（BSA-Au / Ag NCs）与组氨酸稳定的金纳米簇（His- Au NCs）。所制备的Au NCs / Au-Ag NCs溶液发出粉红色荧光，并在485和660 nm处被370 nm激发而出现两个发射峰。在存在Hg2 +的情况下，Au NCs / Au-Ag NCs系统在660 nm处的荧光明显被猝灭，而在485 nm处的荧光对Hg2 +却是稳定的，从而导致荧光强度比（I660 / I485）降低。系统。Hg2 +的检出限低至1.56 nM。随着Fe3 +的加入，系统中Au NCs / Au-Ag NCs的双发射峰同时以不同的速率同时显着下降，导致Fe3 +离子浓度随I660 / I485值的变化而变化。Fe3 +的线性检测范围是5至1000μM。此外，已开发的荧光方法已被用于分别分析鱼样品中不同离子Hg2 +和Fe3 +的分析，结果令人满意。