Inhibition of Sodium Hypochlorite Antimicrobial Activity in the Presence of Bovine Serum Albumin
published online 07 December 2009.
Abstract
Introduction
This study investigated the inhibition of the antimicrobial activity of sodium hypochlorite (NaOCl) by bovine serum albumin (BSA). The killing of Enterococcus faecalis, Candida albicans, Staphylococcus epidermidis, and Escherichia coli by NaOCl in concentrations from 2% to 0.03% was measured in the presence of BSA in concentrations between 6.7% and 0.1%.
Methods
NaOCl, BSA, and microorganism suspensions were mixed, and, after 30 seconds, 6 minutes, and 30 minutes, samples were taken and NaOCl was inactivated by 5% sodium thiosulphate. The microbes were incubated in tryptic soy broth broth for up to 7 days for the detection of growth.
Results
All microorganisms were killed within 30 seconds by 0.03% NaOCl when BSA was not present. High concentrations of BSA significantly reduced the antimicrobial activity of NaOCl against the four species.
Conclusions
The inhibition of sodium hypochlorite by BSA was directly dependent on their quantitative relationships. The result partly explains the poorer performance in vivo of NaOCl as compared to in vitro experiments.
∗Department of Semiology and Clinics, Faculty of Dentistry, Federal University of Pelotas, Pelotas, Brazil
†Department of Restorative Dentistry, Faculty of Dentistry of Araraquara, State University of São Paulo, Araraquara, São Paulo, Brazil
‡Department of Oral Biological and Medical Sciences, Faculty of Dentistry, University of British Columbia, British Columbia, Vancouver, Canada
§Department of Pediatric, Preventive and Community Dentistry, Ribeirão Preto Faculty of Dentistry, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
Address requests for reprints to Dr Fernanda Geraldes Pappen, Division of Endodontics, UFPel- Faculty of Dentistry, Federal University of Pelotas, Rua Sete de Setembro, 43/1101, Pelotas, RS, CEP 96015-300.
Supported by MEC/CAPES (Foundation for the Coordination of Higher Education and Graduate Training in Brazil) as an exchange Scholarship (BEX 4146-06/9).
ABSTRACT