title: Automation of antimicrobial activity screening.
abstract: Manual and automated methods were compared for routine screening of compounds for antimicrobial activity. Automation generally accelerated assays and required less user intervention while producing comparable results. Automated protocols were validated for planktonic, biofilm, and agar cultures of the oral microbe Streptococcus mutans that is commonly associated with tooth decay. Toxicity assays for the known antimicrobial compound cetylpyridinium chloride (CPC) were validated against planktonic, biofilm forming, and 24 h biofilm culture conditions, and several commonly reported toxicity/antimicrobial activity measures were evaluated: the 50 % inhibitory concentration (IC50), the minimum inhibitory concentration (MIC), and the minimum bactericidal concentration (MBC). Using automated methods, three halide salts of cetylpyridinium (CPC, CPB, CPI) were rapidly screened with no detectable effect of the counter ion on antimicrobial activity.
authors.affiliation: Biosystems and Biomaterials Division, National Institutes of Standard and Technology, Gaithersburg, MD, 20899, USA. sam.forry@nist.gov.
authors.forename: Samuel P
authors.initials: SP
authors.lastname: Forry
authors.affiliation: Biosystems and Biomaterials Division, National Institutes of Standard and Technology, Gaithersburg, MD, 20899, USA.
authors.forename: Megan C
authors.initials: MC
authors.lastname: Madonna
authors.affiliation: Biosystems and Biomaterials Division, National Institutes of Standard and Technology, Gaithersburg, MD, 20899, USA.|Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, MD, 20993, USA.
authors.forename: Daneli
authors.initials: D
authors.lastname: López-Pérez
authors.affiliation: Biosystems and Biomaterials Division, National Institutes of Standard and Technology, Gaithersburg, MD, 20899, USA.
authors.forename: Nancy J
authors.initials: NJ
authors.lastname: Lin
authors.affiliation: Biosystems and Biomaterials Division, National Institutes of Standard and Technology, Gaithersburg, MD, 20899, USA.
authors.forename: Madeleine D
authors.initials: MD
authors.lastname: Pasco
keywords: Antimicrobial activity screening; Automation; Performance assessment