Novel application of in vitro disinfection for modeling the biofilm formation inhibition, antimicrobial susceptibility and antibiotic resistance of Pseudomonas aeruginosa: a study of free and combined chlorine compounds – PubMed (

Published on 07/20/2022 | by Waterline Admin

Nabizadeh Nodehi R, Golpayegani A, Douraghi M, Alimohammadi M, Rezaei F. Novel application of in vitro disinfection for modeling the biofilm formation inhibition, antimicrobial susceptibility and antibiotic resistance of Pseudomonas aeruginosa: a study of free and combined chlorine compounds. J Environ Health Sci Eng. 2022 Jan 18;20(1):167-180. doi: 10.1007/s40201-021-00764-0. PMID: 35669826; PMCID: PMC9163233.



  • Biofilm formation and antibiotic resistance are the most important ways in which water bacteria such as Pseudomonas aeruginosaare protected against antibacterial agents.
  • The aim of this study was to develop a rapid and cost-effective laboratory method for modeling and optimizing chlorine disinfection conditions.
  • Critical factors (disinfection type, concentration, contact time and pH) were tested on bactericidal effect, inhibition of biofilm formation (IBF) and antibiotic susceptibility (AS) of  aeruginosa.
  • Optimization of factors affecting disinfection had a significant effect on the planktonic form, but was not effective in removing the biofilm of  aeruginosa.
  • The use of chlorine compounds based on the recommended levels in water does not prevent the formation of  aeruginosabiofilm.
  • Increasing the contact time and concentration of the disinfectant increases the bactericidal effect of chlorine, it can also increase the resistance of  aeruginosato some antibiotics.



Diary Dates & Events

Grime Scene


Following on from the successful Grime Scene competition, we have decided to continue the theme for another year, but with a twist. This year, we are asking for photographs of the grimiest pictures you can find accompanied with another photograph of how the ‘scene’ has been improved by your maintenance or cleaning.

We will display the photographs in each of the Waterline editions throughout 2024. The ‘most improved’ picture will be chosen by WMSoc members via an online vote. The winner will receive a £25 Amazon Gift Voucher after the Winter 2024/25 edition has been published.

Please send your photographs to:
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