State of the Art on Green Route Synthesis of Gold/Silver Bimetallic Nanoparticles

Abstract

Recently, bimetallic nanoparticles (BMNPs) blending the properties of two metals in one nanostructured system have generated enormous interest due to their potential applications in various fields including biosensing, imaging, nanomedicine, and catalysis. BMNPs have been developed later with respect to the monometallic nanoparticles (MNPs) and their physicochemical and biological properties have not yet been comprehensively explored. The manuscript aims at collecting the main design criteria used to synthetize BMNPs focusing on green route synthesis. The influence of experimental parameters such as temperature, time, reagent concentrations, capping agents on the particle growth and colloidal stability are examined. Finally, an overview of their nanotechnological applications and biological profile are presented.

Supramolecular assembly of pentamidine and polymeric cyclodextrin bimetallic core–shell nanoarchitectures

“…The inactivity of nanoG and nanoGS emerged in our work suggested that leishmanicidal effects described in the literature for MNPs or BMNPs [ 2 , 22 – 23 29 ] could be ascribed to their synergistic interactions with the phenolic components of natural extracts used as capping agents. Moreover, we supposed that, in nanoGSP, strong interactions between nanoGS and Pent, assisted by the CD cavities, prevented the release of Pent within 24 h. This is the time of the in vitro biological test and the activity of Pent included into the CD cavity should be better evaluated in vivo according to the literature [ 27 ].…”

“…Noble metal nanoparticles (NPs), in particular those composed of gold and/or silver, are versatile agents endowed with unique physicochemical properties, which recently have drawn great interest for a variety of applications ranging from catalysis to nanomedicine [1][2][3].…”

“…Au/Ag BMNPs with different structural motifs and biological properties have been produced via eco-friendly synthesis using natural extracts or natural compounds which act as both reducing and capping agents [ 2 ]. When these green methods are used to obtain metallic NPs, particle growth, colloidal stability, as well as the biological profile of the resulting products are generally attributed to the phenolic and/or the carbohydrate components of the capping natural source [ 12 ].…”

“…In this case, the inner Au component favors cellular entry (typically via endocytosis) and slow release of the Ag + ions, to which the overall biological activity of the system is ascribed. It all comes down to greater system biocompatibility [ 2 ].…”

Green Chemistry and Molecularly Imprinted Membranes

“…Other green approaches are microwave-assisted and ultrasound-assisted processes [ 46 , 47 , 48 ], hydro/solvo thermal reactions [ 49 , 50 ], magnetic field-assisted synthesis [ 51 ], mechanochemistry [ 52 ], and UV irradiation [ 53 , 54 ]. All these approaches and the evolution of GC have been accurately reviewed [ 1 , 55 , 56 , 57 , 58 , 59 , 60 , 61 ], highlighting that over the last 20 years, the principles of green chemistry have strengthened the environmental sustainability of chemical processes.…”