Resumen
Silver nanoparticles (AgNPs) had been widely synthesized and studied partly due to its antimicrobial properties that can be incorporated in footwear, paint, wound dressing, appliances and plastics. Three methods that can be used to synthesized silver nanoparticles are physical, chemical and biological methods. The physical and chemical methods usually are costly and involve the use of toxic chemicals. Therefore, low-cost and less toxic bio-inspired synthesis of silver nanoparticles by using plant as reducing agent had been intensively studied. In this work, silver nanoparticles (AgNPs) were synthesized by using pomelo (Citrus grandis) peel extract as natural reducing agent which reduces silver ions (Ag+) and lead to the formation of metallic silver (Ag0). The synthesized AgNPs were then characterized by UV-visible spectroscopy (UV-Vis), Fourier transform infra-red spectroscopy (FTIR), field emission scanning microscopy (FESEM) and energy dispersive x-ray (EDX) analyses. The resulting UV-Vis spectra of synthesized AgNPs from pomelo peel extract showed standard surface plasmon resonance band in range of 401-433nm which indicated the presence of AgNPs. FTIR spectra confirm the existence of possible functional groups in pomelo peel extract that responsible for the reduction of nanoparticles. Most of the synthesized AgNPs were observed in spherical shape with size ranging from 22.19 ? 32.58 nm under the field emission scanning electron microscope. The EDX analysis showed the strong signal from the silver atoms in the synthesized nanoparticles which confirmed that the synthesis of AgNPs was successful. The antimicrobial properties of synthesized silver nanoparticles were assessed by determination of their minimum inhibitory concentrations (MIC) against both Gram positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. As a result, the synthesized silver nanoparticles exhibited maximum zone of inhibition of 8 mm and 6 mm against Staphylococcus aureus and Escherichia coli, respectively.