Aims: The representativeness of the mandatory bacterial strains specified in European standards for in vitro assay of the bactericidal activity of antiseptics was evaluated by testing the activity of an antiseptic com...Aims: The representativeness of the mandatory bacterial strains specified in European standards for in vitro assay of the bactericidal activity of antiseptics was evaluated by testing the activity of an antiseptic combining chlorhexidine digluconate 0.2% and benzalkonium chloride 0.5% against 21 additional bacterial strains, and the positive interaction between these two biocidal agents was assessed. Methods and Results: The bactericidal activity of the antiseptic solution used pure or diluted was assessed according to the European standards EN 1040 and EN 13727. The contact time was 1 min at 20°C. Interfering substances used in the EN 13727 assay were bovine serum albumin and sheep erythrocytes, simulating “dirty” conditions, and hard water. A reduction of colony-forming units by ≥5 log10 was deemed to meet the requirements to conclude bactericidal activity. Under “basic” conditions, the bactericidal activity of the antiseptic was observed against all four mandatory strains specified in the standards as well as against nearly all the additional strains tested, including most of those with acquired antibiotic-resistance. The positive interaction between the two biocidal agents was also confirmed. Under “dirty” conditions, the bactericidal activity of the antiseptic solution was maintained against all the mandatory strains and was reduced against only four of the additional strains tested. Conclusions: With regard to the antiseptic tested and under the experimental conditions described, bactericidal activity evidenced against the mandatory strains appeared to be representative of that manifested against a wide range of the main pathogenic bacteria. Reduced bacterial activity against some of the additional strains tested (e.g. Enterobacteriaceae) was observed under “dirty” conditions. Significance and Impact of the Study: EN 13727 with some experimental adjustments represents an additional appropriate standard that needs to be considered for mucocutaneous antiseptic assessment. However, it may be worth including other specific bacterial strains to those specified in the standard, when evaluating antiseptics intended for use in certain clinical situations.展开更多
Aims: The representativeness of European standards phase 2, step 1 regarding bactericidal and yeasticidal activities was used for the comparison of two marketed antiseptic solutions, one containing chlorhexidine diglu...Aims: The representativeness of European standards phase 2, step 1 regarding bactericidal and yeasticidal activities was used for the comparison of two marketed antiseptic solutions, one containing chlorhexidine digluconate (0.5%) and the other combining chlorhexidine digluconate (0.25%), benzalkonium chloride (0.025%) and benzylic alcohol (4%). Methods: The bactericidal activity of the antiseptic solutions used pure or diluted was assessed according to the European standards NF EN 13727 and NF EN 13624 for the bactericidal and yeasticidal activity respectively. The contact time was 1 min at 20°C. Interfering substances used correspond to soiling conditions i.e. bovine serum albumin and sheep erythrocytes. A reduction of colony-forming units by ≥5 log10 was deemed to meet the requirements to conclude bactericidal activity and ≥4 log10 for yeasticidal activity. Results: Regarding all the mandatory strains, both solutions are bactericidal and yeasticidal even after a 40% dilution and even under “dirty” conditions. Conclusions: The present study demonstrated the efficient bactericidal and yeasticidal activity of aqueous solutions containing chlorhexidine digluconate either alone at a concentration of 0.5% (w/v) or at a concentration of 0.25% (w/v) when combined with benzalkonium chloride at 0.025% (w/v) and benzylic alcohol 4%. These results have to be considered regarding the respective formulations and potent allergy risks.展开更多
文摘Aims: The representativeness of the mandatory bacterial strains specified in European standards for in vitro assay of the bactericidal activity of antiseptics was evaluated by testing the activity of an antiseptic combining chlorhexidine digluconate 0.2% and benzalkonium chloride 0.5% against 21 additional bacterial strains, and the positive interaction between these two biocidal agents was assessed. Methods and Results: The bactericidal activity of the antiseptic solution used pure or diluted was assessed according to the European standards EN 1040 and EN 13727. The contact time was 1 min at 20°C. Interfering substances used in the EN 13727 assay were bovine serum albumin and sheep erythrocytes, simulating “dirty” conditions, and hard water. A reduction of colony-forming units by ≥5 log10 was deemed to meet the requirements to conclude bactericidal activity. Under “basic” conditions, the bactericidal activity of the antiseptic was observed against all four mandatory strains specified in the standards as well as against nearly all the additional strains tested, including most of those with acquired antibiotic-resistance. The positive interaction between the two biocidal agents was also confirmed. Under “dirty” conditions, the bactericidal activity of the antiseptic solution was maintained against all the mandatory strains and was reduced against only four of the additional strains tested. Conclusions: With regard to the antiseptic tested and under the experimental conditions described, bactericidal activity evidenced against the mandatory strains appeared to be representative of that manifested against a wide range of the main pathogenic bacteria. Reduced bacterial activity against some of the additional strains tested (e.g. Enterobacteriaceae) was observed under “dirty” conditions. Significance and Impact of the Study: EN 13727 with some experimental adjustments represents an additional appropriate standard that needs to be considered for mucocutaneous antiseptic assessment. However, it may be worth including other specific bacterial strains to those specified in the standard, when evaluating antiseptics intended for use in certain clinical situations.
文摘Aims: The representativeness of European standards phase 2, step 1 regarding bactericidal and yeasticidal activities was used for the comparison of two marketed antiseptic solutions, one containing chlorhexidine digluconate (0.5%) and the other combining chlorhexidine digluconate (0.25%), benzalkonium chloride (0.025%) and benzylic alcohol (4%). Methods: The bactericidal activity of the antiseptic solutions used pure or diluted was assessed according to the European standards NF EN 13727 and NF EN 13624 for the bactericidal and yeasticidal activity respectively. The contact time was 1 min at 20°C. Interfering substances used correspond to soiling conditions i.e. bovine serum albumin and sheep erythrocytes. A reduction of colony-forming units by ≥5 log10 was deemed to meet the requirements to conclude bactericidal activity and ≥4 log10 for yeasticidal activity. Results: Regarding all the mandatory strains, both solutions are bactericidal and yeasticidal even after a 40% dilution and even under “dirty” conditions. Conclusions: The present study demonstrated the efficient bactericidal and yeasticidal activity of aqueous solutions containing chlorhexidine digluconate either alone at a concentration of 0.5% (w/v) or at a concentration of 0.25% (w/v) when combined with benzalkonium chloride at 0.025% (w/v) and benzylic alcohol 4%. These results have to be considered regarding the respective formulations and potent allergy risks.
