A research team, led by The University of Manchester in collaboration with industrial partner Arxada and scientists from the Science and Technology Facilities Council’s (STFC) ISIS Neutron and Muon Source, has investigated the mechanisms by which disinfectants combat infection.
The study, published in the Journal of Colloid and Interface Science, examined the antimicrobial activity of two disinfectant surfactants: cationic didecyldimethyl ammonium chloride (DDAC) and non-ionic hexaethylene glycol monododecyl ether (C12E6) against Gram-negative bacteria.
The findings indicate that C12E6 binds to the outer membrane and partially inserts into the inner membrane of Gram-negative E. coli, causing mild destabilisation. In contrast, DDAC strongly binds to and inserts into both outer and inner membranes, leading to effective membrane leakage and cell damage.
When combined, C12E6 facilitates the insertion of DDAC, which enhances membrane disruption. However, an excessive amount of C12E6 was found to decelerate the bacteria-killing power of DDAC.
Professor Jian Lu, lead author of the paper, stated that the revealed molecular interactions help to understand the roles of different surfactants in formulated products, linking their membrane disruptive behaviour with antimicrobial efficacy. This research could pave the way for new product formulations in the fight against antimicrobial resistance.