Synthesis of bimetallic gold/silver nanoparticles via in situ seeding

Abstract

A way of synthesizing bimetallic gold/silver nanoparticles with in situ seeding initiated by the addition of sodium borohydride is proposed. The obtained nanoparticles are studied by means of transmission electron microscopy (TEM). Changes in the optical density spectra of the nanoparticles during their coagulation are investigated. The technique allows the rapid acquisition of nontoxic SERS-active nanoparticles with maximum SERS enhancement factor about 10 5 in the near infrared range for Raman shifts typical for biological objects such as bacterial cells and spores.

Amplification of surface-enhanced Raman scattering by the oxidation of capping agents on gold nanoparticles

“…The rate constant may also be increased due to photothermal effects in the vicinity of the nanoparticle surfaces, because aggregated nanoparticles demonstrate absorption at the excitation wavelength (785 nm). 36,37 As a result of the interplay between these factors, the SERS intensity increased for all major peaks in the crystal violet spectrum (Fig. 6).…”