In this paper, a multifunctional water-soluble fluorescent probe ANS was designed and synthesized using 1,8-naphthimide as a fluorescent moiety. In HEPES buffer solution at pH 7.4, probe could specifically detect Hg²⁺ and FA with high sensitivity, good immunity to interference, and remarkable visualization, respectively. ANS could complex with Hg²⁺ in a 1:1 ratio with a complexation constant of 5.96 × 10⁴ M^-1, and result in a violet fluorescence at 402 nm, detection limit reach to 4.53 × 10^-8 mol/L. In addition, hydrazine group in its structure could condense with FA to form a hydrazone derivative, at an excitation wavelength of 448 nm that could induce a yellow fluorescence at 550 nm with a detection limit of 2.85 × 10^-7 mol/L. The detection mechanism of the probe for Hg²⁺ and formaldehyde was verified by DFT density functional theory calculations. Finally, the successful applications of ANS in the detection of test strips, seafood, real water samples, and biological cell imaging show that the versatility and high efficiency of ANS provide new possibilities for environmental monitoring, food safety, and medical diagnosis with broad application prospects.

Keywords: 1,8-Naphthalimide; Fluorescent probe; Formaldehyde; Hg(2+); Water solubility.

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本文设计并合成了以1,8-萘酰亚胺为荧光基团的多功能水溶性荧光探针ANS。在pH值为7.4的HEPES缓冲溶液中，该探针能够特异性地检测汞离子（Hg²⁺）和甲醛（FA），具有高灵敏度、良好的抗干扰能力和显著的可视化效果。与Hg²⁺形成1:1复合物时，ANS的结合常数为5.96 × 10⁴ M^-1，产生402 nm处的紫光荧光，检出限可达4.53 × 10^-8 mol/L。此外，其结构中的肼基可以与甲醛缩合形成腙衍生物，在448 nm激发波长下，可引发550 nm处的黄光荧光，检测限为2.85 × 10^-7 mol/L。通过DFT（密度泛函理论）计算验证了探针检测Hg²⁺和甲醛的机理。最后，在试纸、海鲜、真实水样以及生物细胞成像中的成功应用表明，ANS的多功能性和高效性为环境监测、食品安全和医学诊断提供了新的可能性，并具有广阔的应用前景。

关键词：1,8-萘酰亚胺；荧光探针；甲醛；Hg(2+)；水溶性。