Surface-enhanced Raman (SERS) spectra of various batches of bacteria adsorbed on silver colloidal nanoparticles were collected to explore the potential of the SERS technique for rapid and routine identification of E. coli and L. monocytogenes cultures. Relative standard deviation (RSD) of SERS spectra from silver colloidal suspensions and ratios of SERS peaks from small molecules (K(3)PO(4)) we...

Recognizing the significance of the life stage of fish for nano-eco-toxicological studies, the acute toxicity of colloidal silver nanoparticles (AgNPs) was tested in three different life stages of rainbow trout. Fishes were exposed to colloidal AgNPs at nominal concentrations of 100, 32, 10, 3.2, 1, 0.32, 0.1, and 0.032 mg/L. The estimated 96 hr LC50 values were 0.25, 0.71, and 2.16 mg/L for th...

Well-defined metallic nanobowls can be prepared by extending the concept of a protecting group to colloidal synthesis. Magnetic nanoparticles are employed as "protecting groups" during the galvanic replacement of silver with gold. The replacement reaction is accompanied by spontantous dissociation of the protecting groups, leaving behind metallic nanobowls.

We present an experimental spectroscopic study of large random colloidal aggregates of silver nanoparticles undergoing local restructuring. We argue that such well-known phenomena as strong fluctuation of local electromagnetic fields, appearance of "hot spots" and enhancement of nonlinear optical responses depend on the local structure on the scales of several nanosphere diameters, rather than ...

According to the increased probability of the presence of nanomaterials in the aquatic ecosystems, the present study examined the toxicity of three engineered silver nanoparticles (AgNPs) as well as silver ions in the Pontogammarus maeoticus, a brackish water benthic organism living in the littoral zone of the Caspian Sea. The animals were acutely exposed to different concentrations of two comm...

Silver nanoparticle therapeutics using symbiotic organisms can offer solutions to the current obstacles in antimicrobial therapies, because of cost-effective and eco-friendly properties over chemical and physical methods. In this study, we aim to synthesize silver nanoparticles using lichen (Parmotrema tinctorum) extract and evaluation of its antibacterial properties. Synthesized silve...

The present work investigates the synthesis of silver nanoparticles (Ag NPs) by biological method using Bacillus thuringiensis. The MIC test was performed to test the inhibitory concentration of AgNO3 against B. thuringiensis and B. subtilis. Silver nanoparticles were successfully synthesized from B. thuringiensis by green synthesis method. The detailed characterization of the Ag NPs was carrie...