In-situ immobilization of pyrithione in cellulose sponge for durable antimicrobial effect

In this work, a method to form a pyrithione salt in situ is described as an antimicrobial treatment in cellulose sponge for consumer use. The efficacy of this treatment was monitored using X-ray microtomography (Micro-CT), a non-destructive X-ray imaging modality. Micro-CT was utilized to examine the internal structure of the treated sponge, and particles were detected in the cellulose consistent with a pyrithione salt, according to H-1 NMR identification. The Micro-CT study showed that the particles were present in the cellulose before and after simulated use, indicating durability of the antimicrobial treatment method with pyrithione. Quantitative analysis of the particles isolated from the Micro-CT datasets using image analysis methods revealed that both the number of particles and the size of the particles decreased with use of the sponge. This suggested that while the pyrithione treatment remained in the sponge after 100 rinses, usage may cause the particles to break down into smaller particles in addition to some loss of particles. Finally, the cellulose sponges before and after use were challenged with two types of bacteria, S. aureus and E. coli, to demonstrate the antimicrobial properties of the sponge. The pyrithione-treated sponges exhibited a reduction in the number of viable cells in both bacteria compared to untreated sponges.

Automated summary

This study describes an antimicrobial treatment method for consumer use in which a pyrithione salt is formed in situ in a cellulose sponge. The efficacy of this treatment was monitored using X-ray microtomography, which revealed the presence of pyrithione particles in the treated sponge. The study also showed that while the pyrithione treatment remained in the sponge after use, the number and size of particles decreased. The pyrithione-treated sponges exhibited antimicrobial properties against bacteria compared to untreated sponges.