1)Application Of Flow Cytometry Combined With Fluorescent Labeling Technique To Detect The Effect Of Chlorhexidine On E.faecalis Biofilm In Vitro2)Case Report

Objective: To detect the effect of chlorhexidine on the biofilm of Enterococcus faecalis(E.faecalis)in vitro by flow cytometry(FCM).Methods: Both 1d and 3w E.faecalis biofilms were cultured in vitro,and biofilm samples were treated with 2% chlorhexidine(CHX)and normal saline solution(NS)for 5 min,then,after culturing for 0d,1d and 7d,the sterilizing effect was observed by flow cytometry after co-staining with PI and SYTO 9.Results: The sterilizing effect against E.faecalis biofilm of 2% CHX was stronger than the saline group with statistically significance(P<0.05);Compared with the biofilm cultured for 1d,the sterilization effect of 2% CHX on the biofilm cultured for 3w was weakened,and the difference was statistically significant(P<0.05);After the biofilms(1d and 3w)were treated with 2% CHX,the proportion of live bacteria in the samples gradually increased with the prolongation of the reculture time.There was no significant difference between the proportion of live bacteria and the normal saline treatment group after 1w of reculture(P>0.05).Conclusion: The chlorhexidine solution has a good sterilizing effect on the Enterococcus faecalis biofilm in different growth stages in vitro,and the sterilizing effect is not completely.