Molecular dynamics simulations were performed to study combinations of [AcO]⁻, [TfO]⁻, [BF₄]⁻, and [PF₆]⁻ anions paired with imidazolium cations of increasing alkyl chain length to elucidate the roles of anions and cations in solvating ibuprofen. Our simulation results revealed that ionic liquids (ILs) with strong ibuprofen solvation capacity should possess strong van der Waals force from cations and strong hydrogen bond (HB) from anions. Accordingly, it was found that ILs containing anions with strong HB acceptability, such as [AcO]⁻ anion, were the best effective solvent for ibuprofen solvation, while the longer alkyl chain in the imidazolium cations decrease the polarity, thus increasing the affinity with ibuprofen. Therefore, it was suggested that the heterocyclic structure of imidazolium cation with moderate polarity and longer alkyl chain is a promising cation candidate, whereas the anions which have a strong HB acceptability and substituents without electron withdrawing groups are beneficial. The obtained results can provide useful information for rational design and selection of new ILs to dissolve insoluble drugs.

中文翻译：

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基于咪唑鎓的离子液体如何溶解难溶的布洛芬？理论研究

进行分子动力学模拟，以研究[AcO] ^-，[TfO] ^-，[BF ₄ ] ^-和[PF ₆ ] ^-阴离子与烷基链长度增加的咪唑鎓阳离子配对的方法，以阐明阴离子和阳离子在溶剂化布洛芬。我们的模拟结果表明，具有强布洛芬溶剂化能力的离子液体（ILs）应该具有来自阳离子的强范德华力和来自阴离子的强氢键（HB）。因此，发现包含[HBO] ^-等的HB吸收性强的阴离子的IL ^。阴离子是布洛芬溶剂化的最佳有效溶剂，而咪唑鎓阳离子中较长的烷基链会降低极性，从而增加与布洛芬的亲和力。因此，建议具有中等极性和较长烷基链的咪唑阳离子的杂环结构是有希望的阳离子候选物，而具有强HB接受性和不具有吸电子基团的取代基的阴离子是有益的。获得的结果可为合理设计和选择新的溶解不溶性白介素提供有用的信息。