A simple and rapid method for optical visualization and quantification of bacteria on textiles.

Area of Science:

• Materials Science
• Microbiology
• Textile Engineering

Background:

• Biocidal coatings are used to prevent bacterial contamination on textiles.
• Health and environmental concerns favor anti-adhesive coatings over biocidal ones.
• Simple, rapid assays are needed to screen anti-adhesive textile coatings.

Purpose of the Study:

• To develop a simple, robust, and rapid assay for assessing bacteria on textiles.
• To enable direct visualization and quantification of bacterial adhesion.
• To investigate both anti-adhesive and biocidal effects using a single detection method.

Main Methods:

• A tetrazolium salt-based assay was developed for direct eye visualization of bacterial presence on textiles.
• Standard curves were generated to correlate staining intensity with bacterial cell numbers.
• The assay was applied to evaluate the efficacy of anti-adhesive (PLUMA) and biocidal (TH22-27) coatings against Pseudomonas aeruginosa and Staphylococcus aureus.

Main Results:

• The assay provides direct visual color changes indicating bacterial presence.
• Detection limits were established for P. aeruginosa (2.5 x 10^6 to 9.4 x 10^8) and S. aureus (1 x 10^6 to 3.3 x 10^8).
• The PLUMA coating demonstrated anti-adhesive properties, reducing bacterial adhesion without killing bacteria.
• The TH22-27 coating exhibited biocidal activity, significantly reducing viable bacterial cell counts.

Conclusions:

• A novel, rapid tetrazolium salt assay facilitates the screening of textile coatings for bacterial interactions.
• This assay can differentiate between anti-adhesive and biocidal mechanisms of action.
• The developed method supports the advancement of functional textile coatings with improved hygiene properties.