Design of a millifluidic device for the evaluation of blue-light disinfection on Pseudomonas aeruginosa PA01 biofilm

Nidia Maldonado Carmona; Murielle Balthazar; Joanne L Fothergill; Nelly Henry

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arXiv · 2311.17788

Design of a millifluidic device for the evaluation of blue-light disinfection on Pseudomonas aeruginosa PA01 biofilm

Nidia Maldonado Carmona·Murielle Balthazar·Joanne L Fothergill·Nelly Henry

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Abstract

Significance: For the first time to our knowledge, a millifluidic device has been designed to observe the effects of blue-light irradiation in Pseudomonas aeruginosa PA01 bacterial biofilm. Approach: A bacterial biofilm is formed under controlled flow of nutrients in microfabricated channels settled on a microscope stage. The setup is devised to apply defined irradiation and evaluate the photo-killing efficiency in situ using video-microscopy and fluorescent probes. Results: We investigated bacterial survival after delivering a precise, controlled and spatially defined blue light dose upon growing biofilm. We demonstrate in this report that the combined use of constitutive GFP and propidium iodide in a millifluidic setup enables to evidence light-induced mortality at the single cell and community level. Conclusions: Real-time monitoring of a bacterial biofilm growing in a millifluidic device after irradiation opens an avenue for a better understanding of the biofilm community response to blue-light, permitting researchers to approach photokilling efficiency of biofilm as a dynamic process.

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Nidia Maldonado Carmona, Murielle Balthazar, Joanne L Fothergill, Nelly Henry. 2023-11-29. Design of a millifluidic device for the evaluation of blue-light disinfection on Pseudomonas aeruginosa PA01 biofilm. https://arxiv.org/abs/2311.17788

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