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Thermal mitigation of Pseudomonas aeruginosa biofilms.

ABSTRACT: Bacterial biofilms infect 2-4% of medical devices upon implantation, resulting in multiple surgeries and increased recovery time due to the very great increase in antibiotic resistance in the biofilm phenotype. This work investigates the feasibility of thermal mitigation of biofilms at physiologically accessible temperatures. Pseudomonas aeruginosa biofilms were cultured to high bacterial density (1.7 × 10(9) CFU cm(-2)) and subjected to thermal shocks ranging from 50°C to 80°C for durations of 1-30 min. The decrease in viable bacteria was closely correlated with an Arrhenius temperature dependence and Weibull-style time dependence, demonstrating up to six orders of magnitude reduction in bacterial load. The bacterial load for films with more conventional initial bacterial densities dropped below quantifiable levels, indicating thermal mitigation as a viable approach to biofilm control.

SUBMITTER: O'Toole A

PROVIDER: S-EPMC4617618 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Thermal mitigation of Pseudomonas aeruginosa biofilms.

O'Toole Ann A Ricker Erica B EB Nuxoll Eric E

Biofouling 20150101 8

Bacterial biofilms infect 2-4% of medical devices upon implantation, resulting in multiple surgeries and increased recovery time due to the very great increase in antibiotic resistance in the biofilm phenotype. This work investigates the feasibility of thermal mitigation of biofilms at physiologically accessible temperatures. Pseudomonas aeruginosa biofilms were cultured to high bacterial density (1.7 × 10(9) CFU cm(-2)) and subjected to thermal shocks ranging from 50°C to 80°C for durations of ...[more]

PMID: 26371591

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