A cube-like Zn(II)–Eu(III) nanocluster 1 (molecular sizes: 1.8 × 2.0 × 2.0 nm) was constructed by the use of a new long-chain Schiff base ligand. It shows a ratiometric fluorescence response to levofloxacin (LFX) with high sensitivity and selectivity, which can be expressed as I_615 nm/I_550 nm = A*[LFX]² + B*[LFX] + C. It is used to quantitatively detect the LFX concentrations in fetal calf serum (FCS) and tablets sold in pharmacy. Filter paper strips bearing 1 can be used to qualitatively detect LFX by a color change to red under a UV lamp. 1 and its hybrid with sodium alginate (SA), 1@SA, display potential applications in the qualitative detection of LFX in FCS and the medicine. The limit of detection of 1 to LFX is as low as 2.1 × 10^–2 nM.

中文翻译：

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基于立方体 Zn(II)-Eu(III) 纳米团簇的左氧氟沙星比率荧光检测：用于血清和药物检测的功能化海藻酸钠薄膜

利用新型长链席夫碱配体构建了立方体状Zn(II)–Eu(III)纳米团簇1 （分子尺寸：1.8×2.0×2.0 nm）。它显示出对左氧氟沙星 (LFX) 的比率荧光响应，具有高灵敏度和选择性，可表示为I _{615 nm} / I _{550 nm} = A *[LFX] ² + B *[LFX] + C。用于定量检测胎牛血清（FCS）和药房出售的片剂中的LFX浓度。滤纸条轴承1可用于通过在紫外灯下颜色变为红色来定性检测 LFX。1及其与海藻酸钠 (SA) 的混合物1 @SA 在 FCS 和药物中 LFX 的定性检测中显示出潜在的应用。1至 LFX的检测限低至 2.1 × 10 ^–2 nM。