Single Step Microwave Assisted Synthesis and Antimicrobial Activity of Silver, Copper and Silver-Copper Nanoparticles

Abstract

Copper and silver nanoparticles were synthesized and characterized in two minutes at 175˚C in a one-step synthesis using a modified polyol (ethylene glycol) method and a microwave heating process. We successfully synthesized spherical Silver (Ag) and Copper nanoparticles (CuNP) with a crystallite size of less than 10 nm, as well as irregular silver-copper nanoparticles (AgCuNP) with a crystallite size of less than 15 nm, as confirmed by X-Ray Diffraction (XRD) and High-Resolution Transmission Electron Microscopy (HRTEM). The successful synthesis of AgCuNP with 1:1 molar ratio and constituted by 51.74% of copper and 48.26% of silver was corroborated using the Energy Dispersive X-ray (EDX) mapping technique. The AgNP and AgCuNP exhibited more stability in suspension, in comparison to CuNP, as observed by continuously monitoring the absorbance with UV-Vis spectroscopy for 12 days. Furthermore, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of AgNP, CuNP, and AgCuNP were determined, against Gram-negative and Gram-positive bacteria, and yeast. The obtained MIC and MBC values indicate that AgCu nanoparticles exhibited bactericidal properties greater than its constituents. On the contrary, antifungal activity of AgCuNP against yeast was not observed.

Antimicrobial Properties of the Ag, Cu Nanoparticle System

“…The most conventional AgCu nanoalloy synthesis method is through the chemical reduction of a solution containing both Ag and Cu salts. Nanoalloys were synthesized from a solution of AgNO 3 and CuSO 4 , using natural reducing agents, such as fruit peel extract [ 224 ], or Azadirachta indica leaf extract [ 225 ], as well as synthetic reducing agents, such as polyvinylpyrrolidone [ 9 ], polyol [ 226 , 227 ], ascorbic acid [ 228 ], dextrose [ 229 ], sodium borohydride [ 190 ], or tartaric acid [ 152 ]. Another study used oleyl amine as both reducing agent and surfactant, to synthesize nanoalloys from a solution of Ag and Cu(I) complexes, which gave a randomly distributed AgCu solid solution [ 230 ].…”

“…Currently proposed theories all have limitation, and cannot explain the antimicrobial activities in all situations. Recently, AgCu nanoalloys were reported to have antimicrobial properties far greater than either Ag or Cu NPs [ 8 , 9 ]. As it is the NP surface that participates in all the proposed mechanisms, it is our position that the physicochemical surface characterization of NPs, particularly their surfaces, will determine the actual reason(s) behind antimicrobial behavior.…”

“…Currently proposed theories all have limitation, and cannot explain the antimicrobial activities in all situations. Recently, AgCu nanoalloys were reported to have antimicrobial properties far greater than either Ag or Cu NPs [8,9]. As it is the NP surface that participates in all the Despite this, their exact antimicrobial mechanisms are still elusive.…”

Ag–Cu Embedded SDS Nanoparticles for Efficient Removal of Toxic Organic Dyes from Water Medium

“…The crystallite size calculated by Scherrer’s formula was almost 8.96018 nm. Reyes-Blas and Maldonado-Luna estimated the average crystallite size at 12.89 ± 2.00 nm considering the peak at 2θ = 38.521° for Ag and 2θ = 44.761° for Cu …”

AgCu NP Formation by the Ag NP Catalysis of Cu Ions at Room Temperature and Their Antibacterial Efficacy: A Kinetic Study

“…There are several methods to prepare AgCu NAs, including chemical reaction [ 16 , 17 ], laser melting in liquids [ 18 , 19 ], electrochemical fabrication [ 20 ], and vacuum sputtering [ 21 ]; more detailed information can be found in recent reviews [ 4 , 22 ]. The chemical reduction reaction is simple and easily mass-produced.…”