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Antimicrobial activity of iron oxide nanoparticle upon modulation of nanoparticle-bacteria interface.

Arakha M, Pal S, Samantarrai D, Panigrahi TK, Mallick BC, Pramanik K, Mallick B, Jha S - Sci Rep (2015)

Bottom Line: Additionally, the nanocrystals obtained were found to have spherical size with 10-20 nm diameter.However, coating with chitosan molecule resulted significant increase in antimicrobial propensity of IONP.The data, altogether, indicated that the chitosan coating of IONP result in interface that enhances ROS production, hence the antimicrobial activity.

View Article: PubMed Central - PubMed

Affiliation: Department of Life Science, National Institute of Technology Rourkela, Odisha 769008, India.

ABSTRACT
Investigating the interaction patterns at nano-bio interface is a key challenge for safe use of nanoparticles (NPs) to any biological system. The study intends to explore the role of interaction pattern at the iron oxide nanoparticle (IONP)-bacteria interface affecting antimicrobial propensity of IONP. To this end, IONP with magnetite like atomic arrangement and negative surface potential (n-IONP) was synthesized by co-precipitation method. Positively charged chitosan molecule coating was used to reverse the surface potential of n-IONP, i.e. positive surface potential IONP (p-IONP). The comparative data from fourier transform infrared spectroscope, XRD, and zeta potential analyzer indicated the successful coating of IONP surface with chitosan molecule. Additionally, the nanocrystals obtained were found to have spherical size with 10-20 nm diameter. The BacLight fluorescence assay, bacterial growth kinetic and colony forming unit studies indicated that n-IONP (<50 μM) has insignificant antimicrobial activity against Bacillus subtilis and Escherichia coli. However, coating with chitosan molecule resulted significant increase in antimicrobial propensity of IONP. Additionally, the assay to study reactive oxygen species (ROS) indicated relatively higher ROS production upon p-IONP treatment of the bacteria. The data, altogether, indicated that the chitosan coating of IONP result in interface that enhances ROS production, hence the antimicrobial activity.

No MeSH data available.


Related in: MedlinePlus

Fluorescence microscopic images of B. subtilis and E. coli in absence and presence of n-IONP and p-IONP.Intact B. subtilis (a-i), B. subtilis in presence of 50 μM of n-IONP (a-ii), and B. subtilis in presence of 50 μM of p-IONP (a-iii), intact E. coli (b-i), E. coli in presence of 50 μM of n-IONP (b-ii), and E. coli in presence of 50 μM of p-IONP (b-iii). The scale bars represent for 20 μm.
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f6: Fluorescence microscopic images of B. subtilis and E. coli in absence and presence of n-IONP and p-IONP.Intact B. subtilis (a-i), B. subtilis in presence of 50 μM of n-IONP (a-ii), and B. subtilis in presence of 50 μM of p-IONP (a-iii), intact E. coli (b-i), E. coli in presence of 50 μM of n-IONP (b-ii), and E. coli in presence of 50 μM of p-IONP (b-iii). The scale bars represent for 20 μm.

Mentions: The antibacterial activity of both NPs resulting from the interaction pattern is further explored using LIVE/DEAD BacLight fluorescence Kit. In principle, LIVE/DEAD BacLight fluorescence kit gives green fluorescence in presence of viable cells, since Syto9, one of the components of the kit, stains the intact membrane of viable cells which has emission in green region. Another component of the kit is propidium iodide which stains dead cells having deformed membrane, and the emission wavelength fall in red region of the visible spectrum29. As shown in Fig. 6, untreated (control) bacterial cells showed green fluorescence inferring presence of 100% viable cells. The n-IONP (50 μM) treated samples showed insignificant fraction (~10%) of non-viable bacterial cells, indicating insignificant antimicrobial activity of n-IONP against B. subtilis and E. coli, at studied concentration. On other hand, p-IONP (50 μM) treated bacterial culture showed 90% of non-viable bacterial cells, which confirmed the significant change in antimicrobial activity of IONP upon chitosan coating.


Antimicrobial activity of iron oxide nanoparticle upon modulation of nanoparticle-bacteria interface.

Arakha M, Pal S, Samantarrai D, Panigrahi TK, Mallick BC, Pramanik K, Mallick B, Jha S - Sci Rep (2015)

Fluorescence microscopic images of B. subtilis and E. coli in absence and presence of n-IONP and p-IONP.Intact B. subtilis (a-i), B. subtilis in presence of 50 μM of n-IONP (a-ii), and B. subtilis in presence of 50 μM of p-IONP (a-iii), intact E. coli (b-i), E. coli in presence of 50 μM of n-IONP (b-ii), and E. coli in presence of 50 μM of p-IONP (b-iii). The scale bars represent for 20 μm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4594095&req=5

f6: Fluorescence microscopic images of B. subtilis and E. coli in absence and presence of n-IONP and p-IONP.Intact B. subtilis (a-i), B. subtilis in presence of 50 μM of n-IONP (a-ii), and B. subtilis in presence of 50 μM of p-IONP (a-iii), intact E. coli (b-i), E. coli in presence of 50 μM of n-IONP (b-ii), and E. coli in presence of 50 μM of p-IONP (b-iii). The scale bars represent for 20 μm.
Mentions: The antibacterial activity of both NPs resulting from the interaction pattern is further explored using LIVE/DEAD BacLight fluorescence Kit. In principle, LIVE/DEAD BacLight fluorescence kit gives green fluorescence in presence of viable cells, since Syto9, one of the components of the kit, stains the intact membrane of viable cells which has emission in green region. Another component of the kit is propidium iodide which stains dead cells having deformed membrane, and the emission wavelength fall in red region of the visible spectrum29. As shown in Fig. 6, untreated (control) bacterial cells showed green fluorescence inferring presence of 100% viable cells. The n-IONP (50 μM) treated samples showed insignificant fraction (~10%) of non-viable bacterial cells, indicating insignificant antimicrobial activity of n-IONP against B. subtilis and E. coli, at studied concentration. On other hand, p-IONP (50 μM) treated bacterial culture showed 90% of non-viable bacterial cells, which confirmed the significant change in antimicrobial activity of IONP upon chitosan coating.

Bottom Line: Additionally, the nanocrystals obtained were found to have spherical size with 10-20 nm diameter.However, coating with chitosan molecule resulted significant increase in antimicrobial propensity of IONP.The data, altogether, indicated that the chitosan coating of IONP result in interface that enhances ROS production, hence the antimicrobial activity.

View Article: PubMed Central - PubMed

Affiliation: Department of Life Science, National Institute of Technology Rourkela, Odisha 769008, India.

ABSTRACT
Investigating the interaction patterns at nano-bio interface is a key challenge for safe use of nanoparticles (NPs) to any biological system. The study intends to explore the role of interaction pattern at the iron oxide nanoparticle (IONP)-bacteria interface affecting antimicrobial propensity of IONP. To this end, IONP with magnetite like atomic arrangement and negative surface potential (n-IONP) was synthesized by co-precipitation method. Positively charged chitosan molecule coating was used to reverse the surface potential of n-IONP, i.e. positive surface potential IONP (p-IONP). The comparative data from fourier transform infrared spectroscope, XRD, and zeta potential analyzer indicated the successful coating of IONP surface with chitosan molecule. Additionally, the nanocrystals obtained were found to have spherical size with 10-20 nm diameter. The BacLight fluorescence assay, bacterial growth kinetic and colony forming unit studies indicated that n-IONP (<50 μM) has insignificant antimicrobial activity against Bacillus subtilis and Escherichia coli. However, coating with chitosan molecule resulted significant increase in antimicrobial propensity of IONP. Additionally, the assay to study reactive oxygen species (ROS) indicated relatively higher ROS production upon p-IONP treatment of the bacteria. The data, altogether, indicated that the chitosan coating of IONP result in interface that enhances ROS production, hence the antimicrobial activity.

No MeSH data available.


Related in: MedlinePlus