Ghosh Sonali, Niu Shanyuan, Yankova Maya, Mecklenburg Matthew, King Stephen M, Ravichandran Jayakanth, Kalia Rajiv K, Nakano Aiichiro, Vashishta Priya, Setlow Peter
Department of Molecular Biology and Biophysics, UConn Health, Farmington, CT, 06030-3305, USA.
Department of Chemistry, School of Health and Natural Sciences, University of Saint Joseph, West Hartford, CT, 06117-2791, USA.
Sci Rep. 2017 Dec 19;7(1):17768. doi: 10.1038/s41598-017-18125-z.
Black silicon (bSi) wafers with a high density of high-aspect ratio nanopillars have recently been suggested to have mechanical bactericidal activity. However, it remains unclear whether bSi with the nanopillars can kill only growing bacterial cells or also dormant spores that are harder to kill. We have reexamined the cidal activity of bSi on growing cells, dormant and germinated spores of B. subtilis, and dormant spores of several other Bacillus species by incubation on bSi wafers with and without nanopillars. We found that the bSi wafers with nanopillars were indeed very effective in rupturing and killing the growing bacterial cells, while wafers without nanopillars had no bactericidal effect. However, bSi wafers with or without nanopillars gave no killing or rupture of dormant spores of B. subtilis, Bacillus cereus or Bacillus megaterium, although germinated B. subtilis spores were rapidly killed. This work lays a foundation for novel bactericidal applications of bSi by elucidating the limits of mechanical bactericidal approaches.
最近有人提出，具有高密度高纵横比纳米柱的黑硅（bSi）晶片具有机械杀菌活性。然而，尚不清楚带有纳米柱的bSi是只能杀死正在生长的细菌细胞，还是也能杀死更难杀死的休眠孢子。我们通过在有无纳米柱的bSi晶片上孵育，重新研究了bSi对枯草芽孢杆菌正在生长的细胞、休眠和萌发的孢子以及其他几种芽孢杆菌属的休眠孢子的杀菌活性。我们发现，带有纳米柱的bSi晶片在破裂和杀死正在生长的细菌细胞方面确实非常有效，而没有纳米柱的晶片则没有杀菌效果。然而，无论有无纳米柱，bSi晶片对枯草芽孢杆菌、蜡状芽孢杆菌或巨大芽孢杆菌的休眠孢子都没有杀灭或破裂作用，尽管萌发的枯草芽孢杆菌孢子会被迅速杀死。这项工作通过阐明机械杀菌方法的局限性，为bSi的新型杀菌应用奠定了基础。
