Fluoroquinolone antibiotics (FQs), a new class of pollutants that seriously threaten human health through environmental and food residues, have aroused wide public concern. However, little attention has been paid to the potential toxicity of FQs' metal complex. Here, we firstly explore the proof-of-concept study of FQs' metal complex to bind bovine serum albumin (BSA) using systematical spectroscopic approaches. In detail, we have found that the complex of Al3+ with gatifloxacin (Al(III)-GFLX complex) can effectively bind to BSA via electrostatic interaction in PBS buffer (pH = 7.4, 1×), resulting in the formation of Al(III)-GFLX-BSA complex. The negative value of ΔG shows that the binding of Al(III)-GFLX complex to BSA is a spontaneous process. Circular dichroism spectra verify that Al(III)-GFLX complex effectively triggers the conformation changes of BSA's secondary structure. It has been proved that the interaction of small molecule with serum albumin has a significant effect on their in vivo biological effects such as absorption, distribution, metabolism, and excretion, and etc. Therefore, the results of this paper may offer a valuable theoretical basis for establishing safety standards of FQs' metal complex to ensure food and environmental health.

中文翻译：

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分析潜在的污染风险Al（III）-GFLX复合物与牛血清白蛋白的相互作用。

氟喹诺酮类抗生素（FQs）是一类新的污染物，通过环境和食物残留物严重威胁人类健康，引起了公众的广泛关注。但是，人们对FQs金属配合物的潜在毒性几乎没有关注。在这里，我们首先使用系统的光谱学方法探索FQs的金属配合物与牛血清白蛋白（BSA）结合的概念验证研究。详细地，我们发现Al3 +与加替沙星的复合物（Al（III）-GFLX复合物）可以通过PBS缓冲液（pH = 7.4，1x）中的静电相互作用有效地与BSA结合，从而形成Al（III） ）-GFLX-BSA复合体。ΔG的负值表明Al（III）-GFLX络合物与BSA的结合是自发过程。圆二色性光谱证实，Al（III）-GFLX络合物有效触发了BSA二级结构的构象变化。事实证明，小分子与血清白蛋白的相互作用对其吸收，分布，代谢和排泄等体内生物学效应具有显着影响。因此，本文的研究结果可提供有价值的理论依据。建立FQs金属复合物的安全标准，以确保食品和环境健康。