Antimicrobial films obtained from latex particles functionalized with quaternized block copolymers

Area of Science:

• Polymer Chemistry
• Materials Science
• Antimicrobial Agents

Background:

• Developing novel antimicrobial materials is crucial for combating infections.
• Amphiphilic block copolymers offer tunable properties for various applications.
• Quaternization is a common strategy to enhance antimicrobial efficacy.

Purpose of the Study:

• To synthesize and characterize novel amphiphilic block copolymers with antimicrobial properties.
• To investigate the impact of quaternization with different alkyl chains on antimicrobial activity and selectivity.
• To develop and evaluate antimicrobial poly(butyl methacrylate) latex particles and films.

Main Methods:

• Atom Transfer Radical Polymerization (ATRP) and copper-catalyzed cycloaddition for copolymer synthesis.
• Quaternization of copolymers using methyl iodide and butyl bromide.
• Antimicrobial activity testing against bacteria (Gram-positive and Gram-negative) and fungi.
• Emulsion polymerization to create functionalized latex particles.
• Film preparation and antimicrobial activity assessment.

Main Results:

• Effective synthesis of amphiphilic block copolymers via simultaneous or two-step approaches.
• Methyl-quaternized copolymers demonstrated enhanced selectivity against Gram-positive bacteria (Staphylococcus aureus, Staphylococcus epidermidis) compared to red blood cells.
• Successful preparation of poly(butyl methacrylate) latex particles and films using the synthesized copolymers as surfactants.
• Antimicrobial activity of films was influenced by copolymer activity and surface segregation.

Conclusions:

• Amphiphilic block copolymers synthesized by ATRP and click chemistry exhibit potent antimicrobial properties.
• The choice of quaternizing agent significantly impacts antimicrobial selectivity and efficacy.
• Functionalized latex particles and films show promise as antimicrobial materials.
• Surface properties play a critical role in the overall antimicrobial performance of the developed materials.