title: Application of a silver coating on plastic biliary stents to prevent biofilm formation: an experimental study using electron microscopy.
abstract: Background and study aims:Biliary stent dysfunction is mainly caused by biliary sludge that forms as a result of bacterial adherence and subsequent biofilm formation on the inner surface of the stent. Silver ions arewell known to have excellent antimicrobial activity against a wide range of microorganisms. In this study, we designed and constructed silver-coated plastic stent (PS) and investigated whether the silver coating prevented bacterial adherence and biofilm formation through the use of electron microscopy.Material and methods:The polyurethane PS with/without silver coating were prepared in 6-inch segments. The silver-based antimicrobial agents were electrostatically applied onto the stent surface. The stents were then immersed for 5 weeks in infected human bile juice obtained from a patient with cholangitis, and electron microscopy was used to investigate the ability of the modified PS to prevent bacterial adherence and biofilm formation.Results:The bacterial flora did not change before and after immersion of stents in both the group with and without silver coating. Electron microscopic observation revealed meshwork-like structures around the bacteria, characteristic of biofilm-forming bacteria, in all stents from the control group (6/6, 100 %). On the other hand, a limited number of bacteria were observed in all stents in the silver-coated group, and no apparent biofilm formation was observed (0/6, 0 %).Conclusions:The significance of the findings from our study is the ability of silver-coated PS to prevent biofilm formation on the stent surface, which results in the prevention of stent occlusion.
authors.affiliation: Gastroenterology, Aizu Medical Center, Fukushima Medical University, Aizuwakamatsu, Japan.
authors.forename: Akane
authors.initials: A
authors.lastname: Yamabe
authors.affiliation: Gastroenterology, Aizu Medical Center, Fukushima Medical University, Aizuwakamatsu, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Irisawa
authors.affiliation: Department of Cell Science, Institute of Biomedical Science, Fukushima Medical University School of Medicine, Fukushima, Japan.
authors.forename: Ikuo
authors.initials: I
authors.lastname: Wada
authors.affiliation: Gastroenterology, Aizu Medical Center, Fukushima Medical University, Aizuwakamatsu, Japan.
authors.forename: Goro
authors.initials: G
authors.lastname: Shibukawa
authors.affiliation: Gastroenterology, Aizu Medical Center, Fukushima Medical University, Aizuwakamatsu, Japan.
authors.forename: Mariko
authors.initials: M
authors.lastname: Fujisawa
authors.affiliation: Gastroenterology, Aizu Medical Center, Fukushima Medical University, Aizuwakamatsu, Japan.
authors.forename: Ai
authors.initials: A
authors.lastname: Sato
authors.affiliation: Gastroenterology, Aizu Medical Center, Fukushima Medical University, Aizuwakamatsu, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Igarashi
authors.affiliation: Gastroenterology, Aizu Medical Center, Fukushima Medical University, Aizuwakamatsu, Japan.
authors.forename: Takumi
authors.initials: T
authors.lastname: Maki
authors.affiliation: Gastroenterology, Aizu Medical Center, Fukushima Medical University, Aizuwakamatsu, Japan.
authors.forename: Koki
authors.initials: K
authors.lastname: Hoshi