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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

n-IONP and p-IONP induced ROS production.Figure 5(a,c) represent change in fluorescence intensity with DCFH-DA oxidation in presence of n-IONP for B. subtilis and E. coli, respectively. Whereas figure 5(b,d) represent DCFH-DA oxidation kinetics in presence of p-IONP for B. subtilis and E. coli, respectively. Each curve represents the average of three independent measurements with corresponding standard error of mean.
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f5: n-IONP and p-IONP induced ROS production.Figure 5(a,c) represent change in fluorescence intensity with DCFH-DA oxidation in presence of n-IONP for B. subtilis and E. coli, respectively. Whereas figure 5(b,d) represent DCFH-DA oxidation kinetics in presence of p-IONP for B. subtilis and E. coli, respectively. Each curve represents the average of three independent measurements with corresponding standard error of mean.

Mentions: Figure 5 shows kinetics of DCFH-DA oxidation on bacterial cell treatment with the NPs. The NPs were added in log phase of bacterial growth. ROS is also produced in culture media in the absence of NP treatment, inferring the production of ROS is natural. Bacteria produces ROS in non-stress condition. The produced ROS in non-stress conditions is counteracted by ROS scavenging enzymes present in bacteria like superoxide dismutase in E. coli. However, presence of both n-IONP (Fig. 5a,c) and p-IONP (Fig. 5b,d) resulted in significant increase in the fluorescence intensity, with relatively higher change in p-IONP presence than n-IONP. The change in the fluorescence intensity is directly correlated with the higher amount of ROS production for both B. subtilis (Fig. 5a,b) and E. coli (Fig. 5c,d) cells. The ROS observation and the growth kinetics study, together, indicated that the ROS production is a reason for antimicrobial activity by both the IONPs. Additionally, it is observed that the amount of ROS produced (as measured from the fluorescence intensity) is higher for p-IONP than n-IONP. The observation rationalized that p-IONP has higher antimicrobial activity than n-IONP.


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)

n-IONP and p-IONP induced ROS production.Figure 5(a,c) represent change in fluorescence intensity with DCFH-DA oxidation in presence of n-IONP for B. subtilis and E. coli, respectively. Whereas figure 5(b,d) represent DCFH-DA oxidation kinetics in presence of p-IONP for B. subtilis and E. coli, respectively. Each curve represents the average of three independent measurements with corresponding standard error of mean.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

f5: n-IONP and p-IONP induced ROS production.Figure 5(a,c) represent change in fluorescence intensity with DCFH-DA oxidation in presence of n-IONP for B. subtilis and E. coli, respectively. Whereas figure 5(b,d) represent DCFH-DA oxidation kinetics in presence of p-IONP for B. subtilis and E. coli, respectively. Each curve represents the average of three independent measurements with corresponding standard error of mean.
Mentions: Figure 5 shows kinetics of DCFH-DA oxidation on bacterial cell treatment with the NPs. The NPs were added in log phase of bacterial growth. ROS is also produced in culture media in the absence of NP treatment, inferring the production of ROS is natural. Bacteria produces ROS in non-stress condition. The produced ROS in non-stress conditions is counteracted by ROS scavenging enzymes present in bacteria like superoxide dismutase in E. coli. However, presence of both n-IONP (Fig. 5a,c) and p-IONP (Fig. 5b,d) resulted in significant increase in the fluorescence intensity, with relatively higher change in p-IONP presence than n-IONP. The change in the fluorescence intensity is directly correlated with the higher amount of ROS production for both B. subtilis (Fig. 5a,b) and E. coli (Fig. 5c,d) cells. The ROS observation and the growth kinetics study, together, indicated that the ROS production is a reason for antimicrobial activity by both the IONPs. Additionally, it is observed that the amount of ROS produced (as measured from the fluorescence intensity) is higher for p-IONP than n-IONP. The observation rationalized that p-IONP has higher antimicrobial activity than n-IONP.

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