Silver nanoparticles synthesized by direct photoreduction of metal salts. Application in surface‐enhanced Raman spectroscopy

Abstract

A simple synthesis method of silver nanoparticles and its application as an active surface-enhanced Raman spectroscopy (SERS) colloid are presented in this work. The photoreduction of AgNO 3 in presence of sodium citrate (NaCit) was carried out by irradiation with different light sources (UV, white, blue, cyan, green, and orange) at room temperature. The evaluation of silver nanoparticles obtained as a function of irradiation time (1-24 h) and light source was followed by UV-visible absorption spectroscopy. This light-modification process results in a colloid with distinctive optical properties that can be related to the size and shape of the particles. The Ag colloids, as prepared, were employed as active colloids in SERS. Pyridine and caffeine were used as test molecules.

Current Development of Silver Nanoparticle Preparation, Investigation, and Application in the Field of Medicine

“…Photoreduction of silver salt in the presence of PVP or citrate by ultraviolet (UV) light is another simple and effective strategy to produce AgNPs [11,13,14]. However, most photoreduction methods still use organic solvents, such as PVP, and are unable to control the size of obtained AgNPs [11,13,14].…”

“…AgNO 3 is the most often used silver salt for these chemical methods of AgNP synthesis due to its low cost and high stability [10]. Generally, a capping agent [e.g., poly(N-vinyl-2pyrrolidone) (PVP)] is used during chemical reduction to stabilize the nanoparticles and prevent them from aggregating [11]. However, reducing agents and organic solvents used in chemical reduction, such as N,Ndimethylformamide, hydration hydrazine, and sodium borohydride, are highly reactive and pose potential environmental and biological risks [12].…”

Quantification of Solid Residues by Raman Spectroscopy

“…This technique has a detection limit about of 10 −6 M [8][9][10]. For the detection of substances diluted to more low concentrations, methods such as the SERS (Surface Enhanced Raman Scattering) have been developed [11,12], which involve complex metallic substrates or synthesis of colloidal suspensions [13,14]. The SERS phenomenon is the enhancement of Raman signal from molecules in the presence of metallic nanostructures which has a detection limit around of 10 −10 M [15,16].…”

Synthesis of silver nanoparticles in NMMO and their in situ doping into cellulose fibers

“…Silver nanoparticles are usually created by reduction of silver nitrate using ascorbic acid; other commonly used reduction agents include ethanol, sodium citrate, ethylene glycol, and sodium borohydride. The reduction of silver ions is also induced by UV radiation (Sato-Berru et al 2009;Courrol et al 2007) or by polysaccharides, including cellulose ; . However, there are no publications on in situ synthesis of silver nanoparticles in the presence of a stabilizer in spinning solution for Lyocell fiber production.…”