title: Comparison of multiple methods for quantification of microbial biofilms grown in microtiter plates.
abstract: In the present study six assays for the quantification of biofilms formed in 96-well microtiter plates were optimised and evaluated: the crystal violet (CV) assay, the Syto9 assay, the fluorescein diacetate (FDA) assay, the resazurin assay, the XTT assay and the dimethyl methylene blue (DMMB) assay. Pseudomonas aeruginosa, Burkholderia cenocepacia, Staphylococcus aureus, Propionibacterium acnes and Candida albicans were used as test organisms. In general, these assays showed a broad applicability and a high repeatability for most isolates. In addition, the estimated numbers of CFUs present in the biofilms show limited variations between the different assays. Nevertheless, our data show that some assays are less suitable for the quantification of biofilms of particular isolates (e.g. the CV assay for P. aeruginosa).
authors.affiliation: Laboratory for Pharmaceutical Microbiology, Ghent University, Harelbekestraat 72, Ghent, Belgium.
authors.forename: Elke
authors.initials: E
authors.lastname: Peeters
authors.forename: Hans J
authors.initials: HJ
authors.lastname: Nelis
authors.forename: Tom
authors.initials: T
authors.lastname: Coenye
mesh_terms: D018441:Biofilms / Q000254:growth & development*; D002176:Candida albicans / Q000502:physiology*; D015169:Colony Count, Microbial; D005452:Fluoresceins / Q000378:metabolism; D005840:Gentian Violet / Q000378:metabolism; D016946:Gram-Negative Aerobic Rods and Cocci / Q000502:physiology*; D006094:Gram-Positive Bacteria / Q000502:physiology*; D008751:Methylene Blue / Q000031:analogs & derivatives; D009930:Organic Chemicals / Q000378:metabolism; D010078:Oxazines / Q000378:metabolism; D013194:Staining and Labeling; D013778:Tetrazolium Salts / Q000378:metabolism; D014966:Xanthenes / Q000378:metabolism
chemical_list: D005452:Fluoresceins; D009930:Organic Chemicals; D010078:Oxazines; C103389:SYTO 9; D013778:Tetrazolium Salts; D014966:Xanthenes; C435946:dimethylmethylene blue; C059087:2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-((phenylamino)carbonyl)-2H-tetrazolium hydroxide; C005843:resazurin; D005840:Gentian Violet; D008751:Methylene Blue; C018506:diacetylfluorescein