Abstract：
An innovative triple optical sensor is presented that utilizes gold nanoclusters (GNCs) stabilized with ciprofloxacin (CIP) and bovine serum albumin (BSA). The sensor is designed to identify three critical metal ions, namely Cu2+, Al3+, and Hg2+. Under 360 nm excitation, the synthesized CIP-BSA-GNCs demonstrate dual fluorescence emission with peaks at 448 nm (blue) and 612 nm (red). The red emission is associated with the interior of the CIP-BSA-GNCs, whereas the blue emission results from the surface-bound CIP molecules. The sensitive and selective fluorescent nanosensor CIP-BSA-GNCs were employed to detect Cu2+, Al3+, and Hg2+ ions. Cu2+ effectively quenched the fluorescence intensity of the CIP-BSA-GNCs at both peaks via the internal charge transfer mechanism (ICT). Cu2+ could be detected within the concentration range 1.13 × 10-3 to 0.05 µM, with a detection limit of 0.34 nM. Al3+ increased the intensity of CIP fluorescence at 448 nm via the chelation-induced fluorescence enhancement mechanism. The fluorescence intensity of the core CIP-BSA-GNCs at 612 nm was utilized as a reference signal. Thus, the ratiometric detection of Al3+ succeeded with a limit of detection of 0.21 nM within the dynamic range 0.69 × 10-3 to 0.07 µM. Hg2+ effectively quenched the fluorescence intensity of the CIP-BSA-GNCs at 612 nm via the metallophilic interaction mechanism. The fluorescence intensity of CIP molecules at 448 nm was utilized as a reference signal. This allowed for the ratiometric detection of Hg2+ with a detection limit of 0.7 nM within the concentration range 2.3 × 10-3 to 0.1 µM.
摘要：
提出了一种创新的三重光学传感器，该传感器利用环丙沙星（CIP）和牛血清白蛋白（BSA）稳定的金纳米簇（GNC）。该传感器旨在识别三种关键金属离子，即Cu2+，Al3+,Hg2+。在360nm激发下,合成的CIP-BSA-GNC表现出双重荧光发射，峰在448nm（蓝色）和612nm（红色）。红色发射与CIP-BSA-GNC的内部有关，而蓝色发射是由表面边界的CIP分子产生的。敏感和选择性的荧光纳米传感器CIP-BSA-GNC用于检测Cu2+，Al3+,和Hg2+离子。Cu2通过内部电荷转移机制（ICT）有效地猝灭了CIP-BSA-GNC在两个峰的荧光强度。在1.13×10-3至0.05µM的浓度范围内可以检测到Cu2，检测限为0.34nM。Al3+通过螯合诱导的荧光增强机制增加了448nm处的CIP荧光强度。在612nm处的coreCIP-BSA-GNC的荧光强度用作参考信号。因此，在0.69×10-3至0.07µM的动态范围内，Al3+的比率检测成功，检测限为0.21nM。Hg2+通过亲金属相互作用机制有效抑制了612nm处CIP-BSA-GNC的荧光强度。在448nm处的CIP分子的荧光强度用作参考信号。这允许在2.3×10-3至0.1μM的浓度范围内以0.7nM的检测极限进行Hg2+的比率检测。
