Influence of physicochemical surface properties on biofilm formation in drinking water distribution systems

In drinking water distribution systems (DWDS) biofilm formation can negatively affect microbiological quality of water and lead to increase in operational and maintenance costs. The primary aim of this thesis was to explore a potential of two anti-adhesive hydrogel-based coatings inspired by applications in the biomedical field as a biofilm control strategy for DWDS sections prone to biofilm formation. Secondly, we aimed to gain more insight into the role of surface properties of polymeric pipe materials commonly utilized in DWDS on adhesion and biofilm development by representative bacteria and drinking water microbial communities. Compared to the macroscopic hydrogel coating described in Chapter 2, a nanogel-based coating showed advantage in terms of its versatility and ease of application. In Chapters 3 and 4, we showed that the nanogel coating can be successfully deposited on various polymeric pipe materials and that its presence on a surface significantly hindered 4 h adhesion and 24 h biofilm formation by pure cultures of Sphingomonas and Pseudomonas bacteria compared to non-coated surfaces. Moreover, as described in Chapter 5, the coating remained effective against biofilm development by drinking water microbial community for 30 days in conditions representative to DWDS. While further investigation is needed, especially with a focus on the coating’s long-term stability and anti-adhesive performance, this PhD research successfully introduces the concept of pipe surface modification as a biofilm control strategy in DWDS.

Dissertation: https://hdl.handle.net/11370/514f6006-b4d8-4ec4-b5dc-50c560442ccf