title: Microbe repelling coated stainless steel analysed by field emission scanning electron microscopy and physicochemical methods.
abstract: Coating of stainless steel with diamond-like carbon or certain fluoropolymers reduced or almost eliminated adhesion and biofilm growth of Staphylococcus epidermidis, Deinococcus geothermalis, Meiothermus silvanus and Pseudoxanthomonas taiwanensis. These species are known to be pertinent biofilm formers on medical implants or in the wet-end of paper machines. Field emission scanning electron microscopic analysis showed that Staph. epidermidis, D. geothermalis and M. silvanus grew on stainless steel using thread-like organelles for adhesion and biofilm formation. The adhesion threads were fewer in number on fluoropolymer-coated steel than on plain steel and absent when the same strains were grown in liquid culture. Psx. taiwanensis adhered to the same surfaces by a mechanism involving cell ghosts on which the biofilm of live cells grew. Hydrophilic (diamond-like carbon) or hydrophobic (fluoropolymer) coatings reduced the adherence of the four test bacteria on different steels. Selected topographic parameters, including root-mean-square roughness (S (q)), skewness (S (sk)) and surface kurtosis (S (ku)), were analysed by atomic force microscopy. The surfaces that best repelled microbial adhesion of the tested bacteria had higher skewness values than those only slightly repelling. Water contact angle, measured (theta (m)) or roughness corrected (theta (y)), affected the tendency for biofilm growth in a different manner for the four test bacteria.
authors: Department of Applied Chemistry and Microbiology, University of Helsinki, P. O. Box 56, 00014 Helsinki, Finland. mari.raulio@helsinki.fi
authors: Mari
authors: M
authors: Raulio
authors: Mikael
authors: M
authors: Järn
authors: Juhana
authors: J
authors: Ahola
authors: Jouko
authors: J
authors: Peltonen
authors: Jarl B
authors: JB
authors: Rosenholm
authors: Sanna
authors: S
authors: Tervakangas
authors: Jukka
authors: J
authors: Kolehmainen
authors: Timo
authors: T
authors: Ruokolainen
authors: Pekka
authors: P
authors: Narko
authors: Mirja
authors: M
authors: Salkinoja-Salonen
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001422:Bacterial Adhesion; D018441:Biofilms / Q000254:growth & development*; D002244:Carbon / Q000494:pharmacology*; D006090:Gram-Negative Bacteria / Q000254:growth & development*; D006094:Gram-Positive Bacteria / Q000254:growth & development*; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D015388:Organelles / Q000648:ultrastructure; D011108:Polymers / Q000494:pharmacology; D013193:Stainless Steel
chemical_list: D000900:Anti-Bacterial Agents; D011108:Polymers; D013193:Stainless Steel; D002244:Carbon