Publications by authors named "Chong Hui Koh"

Cationic polymers have emerged as promising next-generation antimicrobial agents, albeit with inherent limitations such as low potency and limited biocompatibility. Classical cationic polymers kill bacteria via physical membrane disruption. We propose a non-classical mechanism of crossing the bacterial plasma membrane barrier, a step required for subsequent inhibition of intracellular targets, by cationic polymers which are carbon acids.

View Article and Find Full Text PDF

Objectives: The rise of MDR Gram-negative bacteria (GNB), especially those resistant to last-resort drugs such as carbapenems and colistin, is a global health risk and calls for increased efforts to discover new antimicrobial compounds. We previously reported that polyimidazolium (PIM) compounds exhibited significant antimicrobial activity and minimal mammalian cytotoxicity. However, their mechanism of action is relatively unknown.

View Article and Find Full Text PDF

The growing prevalence of antimicrobial drug resistance in pathogenic bacteria is a critical threat to global health. Conventional antibiotics still play a crucial role in treating bacterial infections, but the emergence and spread of antibiotic-resistant micro-organisms are rapidly eroding their usefulness. Cationic polymers, which target bacterial membranes, are thought to be the last frontier in antibacterial development.

View Article and Find Full Text PDF

For a myriad of different reasons most antimicrobial peptides (AMPs) have failed to reach clinical application. Different AMPs have different shortcomings including but not limited to toxicity issues, potency, limited spectrum of activity, or reduced activity in situ. We synthesized several cationic peptide mimics, main-chain cationic polyimidazoliums (PIMs), and discovered that, although select PIMs show little acute mammalian cell toxicity, they are potent broad-spectrum antibiotics with activity against even pan-antibiotic-resistant gram-positive and gram-negative bacteria, and mycobacteria.

View Article and Find Full Text PDF

Contact lenses are medical devices commonly used to correct refractive errors and to maintain ocular health. Microorganisms such as bacteria that grow on the lens surface cause irritation to the eyes and can even cause loss of vision. In this paper, two different coating strategies are employed to form an efficient antimicrobial coating on contact lenses.

View Article and Find Full Text PDF