环丙沙星在生物碳表面吸附的阳离子-π型机理研究

Sorption mechanism study on antibiotics by biochar is essential to fully understand their environmental behavior. Current main sorption mechanisms cannot well describe the behavior of ionizable antibiotics. Via literature reviewing, we found cation-π interaction which is important in biochemical process, might also be an important mechanism of cation antibiotic sorption on biochars that have aromatic structures. In this study, we selected ciprofloxacin (CIP) as model compound and graphite/graphene as model sorbents, to quantitively study the relative contribution of cation-π interaction to sorption. We will conduct bicompetive and sequentially competitive experiments to compare cation-π interaction’s contribution to the other interactions (e.g. hydrophobic and π–π interactions); Via quantum chemical calculation, we will study the main sorption mechanisms of different CIP dissociate species from a molecular prospect; By analyzing CIP species and energy transformation, we will disclose species transformative sorption mechanism. The results of this study might provide evaluation methods for antibiotics ecological risk assessments, and will provide theoretical basis for preventing and remediating antibiotics in soil and water.

开展生物碳对抗生素吸附机理的研究，对于深入认识抗生素的环境行为具有重要意义。目前已知的主要吸附机理并不能很好的描述离子型抗生素的环境行为。我们发现生化过程中广泛存在的阳离子-π作用可能是阳离子型抗生素在具有芳香性的生物碳表面吸附的重要机制。本项目为了定量分析阳离子-π作用的贡献，揭示吸附机理，选取环丙沙星(CIP)，作为目标化合物，以石墨、石墨烯作为模型吸附剂。通过两两竞争、逐级竞争实验，定性、定量地比较阳离子-π作用与其它作用(如疏水和π–π)的贡献；通过量子化学计算，从分子水平探讨CIP不同解离形态的主要吸附机理；通过分析吸附过程的抗生素形态及能量转化，揭示CIP形态转化吸附机理。本研究的结果可为该类污染物的生态风险评价提供预测方法，为制定土壤和水体中抗生素的防控和治理措施提供理论依据。

开展生物碳对抗生素吸附机理的研究，对于深入认识抗生素的环境行为具有重要意义。目前已知的主要吸附机理并不能很好的描述离子型抗生素的环境行为。本项目选取环丙沙星(CIP)作为目标化合物，以石墨、石墨烯作为模型吸附剂。研究发现生化过程中广泛存在的阳离子-π作用是阳离子型抗生素在具有芳香性的生物碳表面吸附的重要机制。通过两两竞争、逐级竞争实验，定性、定量地比较了阳离子-π作用与其它作用(如疏水和π–π)对总吸附的贡献；通过量子化学计算，从分子水平探讨CIP不同解离形态的主要吸附机理；通过分析吸附过程的抗生素形态及能量转化，揭示了CIP形态转化吸附机理。本研究的结果可为该类污染物的生态风险评价提供预测方法，为制定土壤和水体中抗生素的防控和治理措施提供理论依据。