The antibacterial activity and mechanism of imidazole chloride ionic liquids on Staphylococcus aureus

Abstract

Ionic liquids (ILs) have garnered increasing attention in the biomedical field due to their unique properties. Although significant research has been conducted in recent years, there is still a lack of understanding of the potential applications of ILs in the biomedical field and the underlying principles. To identify the antibacterial activity and mechanism of ILs on bacteria, we evaluated the antimicrobial potency of imidazole chloride ILs (CnMIMCl) on Staphylococcus aureus (S. aureus). The toxicity of ILs was positively correlated to the length of the imidazolidinyl side chain. We selected C12MIMCl to study the mechanism of S. aureus. Through the simultaneous change in the internal and external parts of S. aureus, C12MIMCl caused the death of the bacteria. The production of large amounts of reactive oxygen species (ROS) within the internal parts stimulated oxidative stress, inhibited bacterial metabolism, and led to bacterial death. The external cell membrane could be destroyed, causing the cytoplasm to flow out and the whole cell to be fragmented. The antibacterial effect of C12MIMCl on skin abscesses was further verified in vivo in mice.

Ionic liquids revolutionizing biomedicine: recent advances and emerging opportunities

“…79 Due to the negative electrostatic charge present on bacterial cell surfaces, 80,81 the cations of ILs can easily affect the bacterial surface. 82,83 Meanwhile, the combination of different cations and anions produces a wide range of ILs with tunable structures, enabling the customization of their properties against bacteria, such as Gram-positive Staphylococcus aureus (S. aureus), Gram-negative Pseudomonas aeruginosa (P. aeruginosa), and Escherichia coli (E. coli). The tunability of ILs makes it possible for them to meet different antibacterial demands.…”

“…4A). 82 Chao et al demonstrated that ILs with longer alkyl chains exhibited enhanced antibacterial effects against S. aureus and E. coli . These effects were attributed to the interplay of hydrophobic and electrostatic interactions between the ILs and bacterial membranes.…”

Biocompatible diimidazolium based ionic liquid systems for enhancing the solubility of paclitaxel

“…As a promising solvent, the properties of ionic liquids (ILs) can be tuned according to the requirements by changing the anion, cation, and functional groups, which makes them attractive for a variety of applications, such as catalysis, 1,2 electrochemistry, 3 extraction, 4,5 and solvents. 6,7 In recent years, ILs have gained significant attention in the field of biopharmaceuticals, 8 such as stabilizers to improve the stability of biomolecules, 9 drug carriers to increase the drug solubility, 10 therapeutic agents for disease treatment, 11 and components in biosensors and diagnostic platforms. 12,13 ILs have the capacity to interact with the solute and co-solvent molecules, which can disrupt existing association and promote the assimilation of the solute.…”

Ionic Liquid Gating Induces Anomalous Permeation through Membrane Channel Proteins

“…25 The scanning electron microscopy experiment shows that a high concen-tration of ILs can destroy the structure of the cell membrane, displaying the potential toxicity of ILs. 26 To characterize the effects of ILs on cell membranes and MCPs, molecular dynamics (MD) simulations are always used, especially considering the nanoscale effect of the interface between ILs and cell membranes. It is shown that electrostatic interaction from ILs could influence protein stability, 27 and the hydrophilic ILs could destroy the structure of α-lactalbumin by forming hydrogen bonds between IL and protein surfaces.…”

“…Recently, infrared spectroscopy experiments suggest that the ILs of [C 10 mim]Cl can induce secondary structural changes in MCP and actin filaments in HeLa cells . The scanning electron microscopy experiment shows that a high concentration of ILs can destroy the structure of the cell membrane, displaying the potential toxicity of ILs . To characterize the effects of ILs on cell membranes and MCPs, molecular dynamics (MD) simulations are always used, especially considering the nanoscale effect of the interface between ILs and cell membranes.…”