Size- and Shape-Dependent Antibacterial Studies of Silver Nanoparticles Synthesized by Wet Chemical Routes.
Silver nanoparticles (AgNPs) of different shapes and sizes were prepared by solution-based chemical reduction routes. Silver nitrate was used as a precursor, tri-sodium citrate (TSC) and sodium borohydride as reducing agents, while polyvinylpyrrolidone (PVP) was used as a stabilizing agent. The morphology, size, and structural properties of obtained nanoparticles were characterized by scanning electron microscopy (SEM), UV-visible spectroscopy (UV-VIS), and X-ray diffraction (XRD) techniques. Spherical AgNPs, as depicted by SEM, were found to have diameters in the range of 15 to 90 nm while lengths of the edges of the triangular particles were about 150 nm. The characteristic surface plasmon resonance (SPR) peaks of different spherical silver colloids occurring in the wavelength range of 397 to 504 nm, whereas triangular particles showed two peaks, first at 392 nm and second at 789 nm as measured by UV-VIS. The XRD spectra of the prepared samples indicated the face-centered cubic crystalline structure of metallic AgNPs. Thein vitroantibacterial properties of all synthesized AgNPs against two types of Gram-negative bacteria,Pseudomonas aeruginosaandEscherichia coliwere examined by Kirby-Bauer disk diffusion susceptibility method. It was noticed that the smallest-sized spherical AgNPs demonstrated a better antibacterial activity against both bacterial strains as compared to the triangular and larger spherical shaped AgNPs.
Centre of Excellence in Solid State Physics, University of the Punjab, QAC, Lahore 54590, Pakistan. akramraza.cssp@pu.edu.pk.
Muhammad Akram
MA
Raza
Department of Zoology, Lahore College for Women University, Jail Road, Lahore 54000, Pakistan. zakia.kanwal@lcwu.edu.pk.
Zakia
Z
Kanwal
Centre of Excellence in Solid State Physics, University of the Punjab, QAC, Lahore 54590, Pakistan. akaramraza.cssp@pu.edu.pk.
Anum
A
Rauf
Department of MicroBiology & Molecular Genetics, University of the Punjab, QAC, Lahore 54590, Pakistan. anjum.mmg@pu.edu.pk.
Anjum Nasim
AN
Sabri
Centre of Excellence in Solid State Physics, University of the Punjab, QAC, Lahore 54590, Pakistan. saira_cssp@yahoo.com.
Saira
S
Riaz
Centre of Excellence in Solid State Physics, University of the Punjab, QAC, Lahore 54590, Pakistan. shahzad.cssp@pu.edu.pk.
Shahzad
S
Naseem
AgNPs; Escherichia coli (E. coli); Pseudomonas aeruginosa (P. aeruginosa); antibacterial activity; reduction method