Synthesis and characterization of lipophilic bismuth dimercaptopropanol nanoparticles and their effects on oral microorganisms growth and biofilm formation Academic Article uri icon


  • The increasing prevalence of resistance among pathogenic microorganisms to common antibiotics has become one of the most significant concerns in modern medicine. Nanotechnology offers a new alternative to develop materials with interesting applications in many areas of biological sciences and medicine. While some bismuth derivatives have been employed to treat vomiting, nausea, diarrhea, and stomach pain, the antimicrobial properties of bismuth in its nanoparticulate form have not been extensively studied. The objective of this investigation was to analyze the bactericidal, fungicidal, and antibiofilm activities of bismuth dimercaptopropanol nanoparticles (BisBAL NPs) against oral microbes. The nanoparticles are composed of 18.7 nm crystallites on average and have a rhombohedral structure, agglomerating into chains-like or clusters of small nanoparticles. Our results showed that stable colloidal BisBAL NPs inhibited Streptococcus mutans and Streptococcus gordonii growth by more than 70 % at 0.1 M, showing a twelve thousand fold higher effectiveness compared with 1.2 mM chlorhexidine, the oral antiseptic most used by dentists. The minimal inhibitory concentration (MIC) of BisBAL NPs for S. mutans and S. gordonii was 5 M. MIC of BisBAL NPs for Candida albicans was 10 M. However, 100 M of BisBAL NPs were required to interfere with planktonic growth of and biofilm formation by a multi-species population of bacteria. Our experiments show that bactericidal activity of BisBAL NPs was similar to antibiotics such as vancomycin and rifampicin. Based on MTT cell viability assays, we hypothesize that BisBAL NPs potentially act on key enzymes, altering their metabolism, and cause cell lysis. All together, these findings show the efficacy of BisBAL NPs as a broad spectrum antimicrobial agent which could reduce antibiotic usage. 2014 Springer Science+Business Media.

published proceedings


altmetric score

  • 3

author list (cited authors)

  • Badireddy, A. R., Hernandez-Delgadillo, R., Sanchez-Najera, R. I., Chellam, S., & Cabral-Romero, C.

citation count

  • 34

complete list of authors

  • Badireddy, Appala Raju||Hernandez-Delgadillo, Rene||Sanchez-Najera, Rosa Isela||Chellam, Shankararaman||Cabral-Romero, Claudio

publication date

  • May 2014