Antibacterial Activity, in Vitro Cytotoxicity, and Cell Cycle Arrest of Gemini Quaternary Ammonium Surfactants

Abstract

Twelve gemini quaternary ammonium surfactants have been employed to evaluate the antibacterial activity and in vitro cytotoxicity. The antibacterial effects of the gemini surfactants are performed on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) with minimum inhibitory concentrations (MIC) ranging from 2.8 to 167.7 μM. Scanning electron microscopy (SEM) analysis results show that these surfactants interact with the bacterial cell membrane, disrupt the integrity of the membrane, and consequently kill the bacteria. The data recorded on C6 glioma and HEK293 human kidney cell lines using an MTT assay exhibit low half inhibitory concentrations (IC50). The influences of the gemini surfactants on the cell morphology, the cell migration ability, and the cell cycle are observed through hematoxylin-eosin (HE) staining, cell wound healing assay, and flow cytometric analyses, respectively. Both the values of MIC and IC50 decrease against the growth of the alkyl chain length of the gemini surfactants with the same spacer group. In the case of surfactants 12-s-12, the MICs and IC50s are found to decrease slightly with the spacer chain length changing from 2 to 8 and again to increase at higher spacer length (s = 10-12). All of the gemini surfactants show great antibacterial activity and cytotoxicity, and they might exhibit potential applications in medical fields.

Highly hydrophilic cationic gold nanorods stabilized by novel quaternary ammonium surfactant with negligible cytotoxicity

“…With regard to a model of cell membranes as a fluid‐like bilayer arrangement of phospholipids, the cytotoxic effect of QAS is generally attributed to their penetration into phospholipids membrane and formation of membrane lipid/protein‐QAS mixed micelles resulting in disruption of cell membrane integrity and membrane ruptures . However, as the cytotoxicity of QAS was observed also at low doses where the cell lysis was not observed , the toxic effects can occur also as a result of membrane potential changes due to blocking of potassium channels , mitochondrial dysfunction or cell cycle arrest .…”

Thiourea and Guanidine Compounds and Their Iridium Complexes in Drug‐Resistant Cancer Cell Lines: Structure‐Activity Relationships and Direct Luminescent Imaging

“…We propose that these differences relate to the impact that the longer chain makes on the hydrophobicity balance of the molecule. The guanidine compounds are expected to be protonated under these conditions, and addition of a long chain will produce a cationic surfactant‐type molecule which could disrupt biological membranes . With other side chains, the charged guanidiniums may not be sufficiently lipophilic to enter the biological membranes when compared to the neutral thioureas.…”

Supramolecular Germicide Switches through Host‐Guest Interactions for Decelerating Emergence of Drug‐Resistant Pathogens

“…In this work, four kinds of commercial germicides with different molecular structure and counterions are selected as representatives, including dodecyl dimethyl benzyl ammonium bromide (DDBAB), dodecyl dimethyl benzyl ammonium chloride, (DDBAC), benzyl‐dimethyl‐hexadecylammonium‐chloride (BCDAC) and dodecyl trimethyl ammonium chloride (DDTMA). These germicides with quaternary ammonium (QA) groups have been widely used for clinical therapy, sewage management, crude oil transportation, etc,, and have proved to be broad‐spectrum antimicrobials against bacteria, fungi, and viruses . CB[7] as a kind of important macrocyclic molecules with excellent biocompatibility has been widely used in supramolecular systems ,.…”

“…Combining 1 H NMR data and ITC results, it is safe to say that the expected germicide switch complexes (Figure ) were constructed accurately. The bactericides bearing quaternary ammonium (QA) could efficiently kill pathogens through electrostatic and hydrophobic interactions with pathogen membrane ,,. It is expected that cationic germicide has different interaction modes with pathogens after the encapsulation of QA groups and hydrophobic groups by CB[7].…”