|报告题目:||Strategies to overcome multidrug-resistant infections: biodegradable antimicrobial polymers|
|报 告 人:||Yi Yan Yang教授（Institute of Bioengineering and Nanotechnology）|
With the increased prevalence of antibiotic-resistant infections and lack of new antibiotics, there is an urgent need for development of innovative antimicrobial agents. Macromolecular antimicrobial agents such as cationic polymers and peptides have recently received increasing attention because they can selectively target and disintegrate bacterial membranes via electrostatic interaction and insertion into the membrane lipid domains, avoiding potential bacterial resistance. Many antimicrobial peptides have seen limited clinical applications in treatment of systemic infections due to enzymatic degradation and toxicity. As a result, a plethora of bio-inspired synthetic polymers have been developed and are achieving considerable success in overcoming many drawbacks found in using peptides.
In this talk, biodegradable antimicrobial polymers will be discussed. The antimicrobial polymers are based on biodegradable cationic polycarbonates, which are synthesized via organocatalytic living ring-opening polymerization. This synthetic platform yields polymers with well-defined molecular weight and structure, which is crucial in the future clinical applications as individual molecular weight fractions of a polydisperse system are expected to exhibit distinct pharmacological activities in vivo. Cationic polycarbonate with various molecular compositions have been designed and synthesized. The polycarbonates with optimal hydrophilicity/hydrophobicity balance have strong activity against multidrug-resistant (MDR) Gram-positive and Gram-negative bacteria as well as fungi without inducing significant toxicity both in vitro and in vivo. The optimized polymers have been tested in MDR MRSA, P. aeruginosa and K. pneumoniae infectious mouse models, and the results are promising. In addition, polyionenes have recently been synthesized, which kill bacteria rapidly and are effective against tuberculosis mycobacteria. Antimicrobial polymers have been formulated into cream, hydrogel and surface coatings for prevention of biofilm formation. These antimicrobial polymers hold potential for use in the prevention and treatment of MDR infections.