Biopolymers Regulate Silver Nanoparticle under Microwave Irradiation for Effective Antibacterial and Antibiofilm Activities.

In the current study, facile synthesis of carboxymethyl cellulose (CMC) and sodium alginate capped silver nanoparticles (AgNPs) was examined using microwave radiation and aniline as a reducing agent. The biopolymer matrix embedded nanoparticles were synthesized under various experimental conditions using different concentrations of biopolymer (0.5, 1, 1.5, 2%), volumes of reducing agent (50, 100, 150 μL), and duration of heat treatment (30 s to 240 s). The synthesized nanoparticles were analyzed by scanning electron microscopy, UV-Vis spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy for identification of AgNPs synthesis, crystal nature, shape, size, and type of capping action. In addition, the significant antibacterial efficacy and antibiofilm activity of biopolymer capped AgNPs were demonstrated against different bacterial strains, Staphylococcus aureus MTCC 740 and Escherichia coli MTCC 9492. These results confirmed the potential for production of biopolymer capped AgNPs grown under microwave irradiation, which can be used for industrial and biomedical applications

Scanning electron microscopic images.

<p>(A) CMC@AgNPs and (B) SA@AgNPs.</p

Ultraviolet–Visible spectroscopy.

<p>(A) CMC@AgNPs at (a) 30s, (b) 60s, (c) 90s, (d) 120s, (e) 150s, (f) 180s, (g) 210s and (h) 240s. (B) SA@AgNPs at (a) 30s, (b) 60s, (c) 90s, (d) 120s, (e) 150s, (f) 180s, (g) 210s and (h) 240s. Arrow indicates direction of spectral changes.</p

Biopolymers Regulate Silver Nanoparticle under Microwave Irradiation for Effective Antibacterial and Antibiofilm Activities - Fig 7

<p><b>(A) Antibiofilm efficacy of</b> CMC@AgNPs <b>and (B)</b> SA@AgNPs <b>against both <i>E</i>. <i>coli</i> and <i>S</i>. <i>aureus</i>.</b> Error bars represent the standard deviation. * Significantly different (P<0.05) from the positive control.</p

Comparison of the microwave assisted methods with other physical methods and summary of their morphological size.

<p>Comparison of the microwave assisted methods with other physical methods and summary of their morphological size.</p

Fourier transform infrared spectra.

<p>(A) CMC—(a) Pure CMC and (b) CMC@AgNPs. (B) SA—(a) Pure SA and (b) SA@AgNPs.</p