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Nitric oxide-releasing porous silicon nanoparticles.

Kafshgari MH, Cavallaro A, Delalat B, Harding FJ, McInnes SJ, Mäkilä E, Salonen J, Vasilev K, Voelcker NH - Nanoscale Res Lett (2014)

Bottom Line: Subsequent reduction of nitrite in the presence of d-glucose led to the production of large NO payloads without reducing the biocompatibility of the PSi NPs with mammalian cells.The resulting PSi NPs demonstrated sustained release of NO and showed remarkable antibacterial efficiency and anti-biofilm-forming properties.These results will set the stage to develop antimicrobial nanoparticle formulations for applications in chronic wound treatment.

View Article: PubMed Central - HTML - PubMed

Affiliation: ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Mawson Institute, University of South Australia, GPO Box 2471 Adelaide, SA 5001, Australia.

ABSTRACT
In this study, the ability of porous silicon nanoparticles (PSi NPs) to entrap and deliver nitric oxide (NO) as an effective antibacterial agent is tested against different Gram-positive and Gram-negative bacteria. NO was entrapped inside PSi NPs functionalized by means of the thermal hydrocarbonization (THC) process. Subsequent reduction of nitrite in the presence of d-glucose led to the production of large NO payloads without reducing the biocompatibility of the PSi NPs with mammalian cells. The resulting PSi NPs demonstrated sustained release of NO and showed remarkable antibacterial efficiency and anti-biofilm-forming properties. These results will set the stage to develop antimicrobial nanoparticle formulations for applications in chronic wound treatment.

No MeSH data available.


Time-based inhibition of S. aureus by NO/THCPSiNPs.S. aureus was treated with glucose/THCPSi NPs (bluecolumns) and NO/THCPSi NPs (orange columns) at different NPconcentrations after (a) 2 h and (b) 4 h(initial bacteria density 104 CFU/mL). Statisticallysignificant inhibition as compared with control(*P < 0.05, **P < 0.01;n = 3; mean ± standarddeviation shown).
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Figure 4: Time-based inhibition of S. aureus by NO/THCPSiNPs.S. aureus was treated with glucose/THCPSi NPs (bluecolumns) and NO/THCPSi NPs (orange columns) at different NPconcentrations after (a) 2 h and (b) 4 h(initial bacteria density 104 CFU/mL). Statisticallysignificant inhibition as compared with control(*P < 0.05, **P < 0.01;n = 3; mean ± standarddeviation shown).

Mentions: Further experiments showed that growth inhibition by NO/THCPSi NPs againstplanktonic S. aureus was evident as early as 2 to 4 h after NPtreatment (Figure 4). After 2 h, the bacterialcounts were reduced by 0.52 log compared to the control (bacteria only), andafter 4 h, a further reduction occurred (1.04 log). In contrast,glucose/THCPSi NPs supported S. aureus proliferation at the sameincubation times. Growth inhibition of S. aureus was sensitive to thedose of NO/THCPSi NPs applied (Figure 4). When higherconcentrations of NO/THCPSi NPs were applied, the S. aureus bacterialload decreased by 1.3 log. It should be noted that a by-product of increasing NPconcentration is glucose supplementation, which may be reflected by the increasein bacterial density in cultures treated with glucose/THCPSi NPs. Culturestreated with NO/THCPSi NPs, however, showed no such upward trend in bacterialgrowth rate, suggesting that the release of NO was able to counter any influencewrought by additional glucose provided by NO/THCPSi NPs. Therefore, theseresults indicate that the NO released form the NO/THCPSi NPs is an effectiveantimicrobial agent against medically relevant Gram-positive and Gram-negativebacteria.


Nitric oxide-releasing porous silicon nanoparticles.

Kafshgari MH, Cavallaro A, Delalat B, Harding FJ, McInnes SJ, Mäkilä E, Salonen J, Vasilev K, Voelcker NH - Nanoscale Res Lett (2014)

Time-based inhibition of S. aureus by NO/THCPSiNPs.S. aureus was treated with glucose/THCPSi NPs (bluecolumns) and NO/THCPSi NPs (orange columns) at different NPconcentrations after (a) 2 h and (b) 4 h(initial bacteria density 104 CFU/mL). Statisticallysignificant inhibition as compared with control(*P < 0.05, **P < 0.01;n = 3; mean ± standarddeviation shown).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4109794&req=5

Figure 4: Time-based inhibition of S. aureus by NO/THCPSiNPs.S. aureus was treated with glucose/THCPSi NPs (bluecolumns) and NO/THCPSi NPs (orange columns) at different NPconcentrations after (a) 2 h and (b) 4 h(initial bacteria density 104 CFU/mL). Statisticallysignificant inhibition as compared with control(*P < 0.05, **P < 0.01;n = 3; mean ± standarddeviation shown).
Mentions: Further experiments showed that growth inhibition by NO/THCPSi NPs againstplanktonic S. aureus was evident as early as 2 to 4 h after NPtreatment (Figure 4). After 2 h, the bacterialcounts were reduced by 0.52 log compared to the control (bacteria only), andafter 4 h, a further reduction occurred (1.04 log). In contrast,glucose/THCPSi NPs supported S. aureus proliferation at the sameincubation times. Growth inhibition of S. aureus was sensitive to thedose of NO/THCPSi NPs applied (Figure 4). When higherconcentrations of NO/THCPSi NPs were applied, the S. aureus bacterialload decreased by 1.3 log. It should be noted that a by-product of increasing NPconcentration is glucose supplementation, which may be reflected by the increasein bacterial density in cultures treated with glucose/THCPSi NPs. Culturestreated with NO/THCPSi NPs, however, showed no such upward trend in bacterialgrowth rate, suggesting that the release of NO was able to counter any influencewrought by additional glucose provided by NO/THCPSi NPs. Therefore, theseresults indicate that the NO released form the NO/THCPSi NPs is an effectiveantimicrobial agent against medically relevant Gram-positive and Gram-negativebacteria.

Bottom Line: Subsequent reduction of nitrite in the presence of d-glucose led to the production of large NO payloads without reducing the biocompatibility of the PSi NPs with mammalian cells.The resulting PSi NPs demonstrated sustained release of NO and showed remarkable antibacterial efficiency and anti-biofilm-forming properties.These results will set the stage to develop antimicrobial nanoparticle formulations for applications in chronic wound treatment.

View Article: PubMed Central - HTML - PubMed

Affiliation: ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Mawson Institute, University of South Australia, GPO Box 2471 Adelaide, SA 5001, Australia.

ABSTRACT
In this study, the ability of porous silicon nanoparticles (PSi NPs) to entrap and deliver nitric oxide (NO) as an effective antibacterial agent is tested against different Gram-positive and Gram-negative bacteria. NO was entrapped inside PSi NPs functionalized by means of the thermal hydrocarbonization (THC) process. Subsequent reduction of nitrite in the presence of d-glucose led to the production of large NO payloads without reducing the biocompatibility of the PSi NPs with mammalian cells. The resulting PSi NPs demonstrated sustained release of NO and showed remarkable antibacterial efficiency and anti-biofilm-forming properties. These results will set the stage to develop antimicrobial nanoparticle formulations for applications in chronic wound treatment.

No MeSH data available.