title: Durability of amide N-chloramine biocides to ethylene oxide sterilization.
abstract: The objective of this work is to study the stability of three novel topical antimicrobial dressings consisting of amide N-chloramine structures against ethylene oxide sterilization. Cotton gauze samples bonded with one of three amide N-chloramine structures were subjected to standard ethylene oxide (EtO) sterilization. The amounts of amide N-chloramine structures before and after the sterilization were quantified to indicate the stabilities of these amide N-chloramine structures to the sterilization. The samples after sterilization were challenged with a clinical isolate of healthcare-associated multidrug-resistant Escherichia coli. N-Chloramine structure converted from polymethacrylamide (dressing 2) had the highest durability (89.7% retained active chlorine) toward EtO sterilization; that from hydantoin (dressing 3; 86.3% retained active chlorine) followed; and poly(N-chloroacrylamide) (dressing 1) had the lowest (64.0% retained active chlorine). After EtO sterilization, all the samples still reduced E. coli presence at 5 minutes of contact, with dressing 2 retaining a log 6 reduction. The three tested amide N-chloramine structures could all survive EtO sterilization while retaining percentages of active chlorine ranging from 64.0 to 89.7%. Dressing 2 showed the best durability, whereas dressing 1 had the poorest durability. With the remaining amounts of amide N-chloramine structures after EtO sterilization, all the dressings could still reduce E. coli numbers within 5 minutes of contact, and dressing 2 resulted in a log 6 reduction in colony count.
authors.affiliation: Department of Textile Sciences, Faculty of Human Ecology, University of Manitoba, Winnipeg, Canada.
authors.forename: Nan
authors.initials: N
authors.lastname: Zhao
authors.forename: Sarvesh
authors.initials: S
authors.lastname: Logsetty
authors.forename: Song
authors.initials: S
authors.lastname: Liu
mesh_terms: D001458:Bandages; D002700:Chloramines / Q000737:chemistry*; D004202:Disinfectants / Q000737:chemistry; D005027:Ethylene Oxide / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D012680:Sensitivity and Specificity; D013242:Sterilization / Q000379:methods*; D013329:Structure-Activity Relationship; D014946:Wound Infection / Q000517:prevention & control
chemical_list: D002700:Chloramines; D004202:Disinfectants; D005027:Ethylene Oxide