High throughput method to determine the surface activity of antimicrobial polymeric materials

Area of Science:

• Materials Science
• Microbiology
• Biotechnology

Background:

• Microbial surface colonization and antibiotic resistance cause significant industrial production failures.
• Self-sterilising materials offer a promising solution for preventing surface colonization.
• Current screening methods for these materials are inefficient, being both laborious and time-consuming.

Purpose of the Study:

• To compare the efficacy of a novel modified solid surface antimicrobial assay against established methods.
• To evaluate the detection capabilities of different antimicrobial assays for various compounds.
• To develop a rapid, high-throughput screening method for self-sterilising materials.

Main Methods:

• Comparison of disk diffusion assay, JIS Z 2801, and a novel resazurin-based solid surface antimicrobial assay.
• Utilisation of antibiotic-containing cellulose disks and four bacterial pathogens.
• Incorporation of the metabolic active dye resazurin to shorten incubation times.

Main Results:

• Disk diffusion assay detected only small, leached compounds over 20-24 hours.
• JIS Z 2801 detected surface activity of non-polar compounds missed by disk diffusion.
• The novel resazurin assay yielded results comparable to JIS Z 2801 in under 4 hours, adaptable to a 96-well plate format.

Conclusions:

• The resazurin-based assay provides a rapid and efficient alternative for screening antimicrobial materials.
• This high-throughput method accelerates the identification of novel self-sterilising materials.
• The assay overcomes limitations of traditional methods, improving the detection of antimicrobial activity on surfaces.