Achieving selective and sensitive carbohydrate-protein interactions (CPIs) using nanotechnology is an intriguing area of research. Here we demonstrate that the different shapes of gold nanoparticles (AuNPs) functionalized with monosaccharides tune the bacterial aggregations. The mechanism of aggregation revealed that the large number of surface interactions of rod shaped mannose-AuNPs with E. c...

Electrochemical and in situ spectroelectrochemical behaviours of phenosafranine (PS + ) were studied at the gold nanoparticles (AuNps) immobilized Nafion (Nf) film coated glassy carbon (GC) and indium tin oxide (ITO) electrodes. Cyclic voltammetric studies showed that the PS + molecules strongly interact with the AuNps immobilized in the Nf matrix through the electrostatic interaction. The pres...

Fluorescence labeling of gold-aryl nanoparticles, AuNPs-COOH, was achieved by the covalent derivatization with dansyl chloride (DNS-Cl) reagent (5-naphthalene-1-sulfonyl chloride) for potential ssDNA recognition. The fluorescent gold nanoparticles AuNPs-C6H4-4-COO-dansyl (AuNPs-DNS) spherical shape and a size 19.3 ± 8.3 nm were synthesized in carbonate-bicarbonate buffer (pH = 10.6) at 37 °C. f...

Nanomaterials may interact with biomolecules in various ways and change their bioactivities. Here, we report on how gold nanoparticles (AuNPs) affect a most important protease, trypsin. After simple mixing of the trypsin and AuNPs solution the average diameter is 20 nm under enzyme friendly conditions (pH 8.0); the bond between trypsin and AuNPs was detected by UV-vis spectroscopy. The further ...

In this study a novel sensitive nanogold particle sensor enhancement based on mixed self-assembled monolayers was explored and used to construct a Surface Plasmon Resonance (SPR) immunosensor to detect Ischemia Modified Albumin (IMA). Compared with a direct binding SPR assay at a limit of detection (LOD) of 100 ng/L, gold nanoparticles (AuNPs) of 10 nm dramatically improved the LOD of IMA to 10...

CO(2)-switchable gold nanoparticles (AuNPs) were prepared by functionalizing AuNPs with CO(2)-switchable polymers. Their dispersion-re-dispersion in and separation from aqueous solution can be easily and reproducibly adjusted by CO(2) bubbling through and removal from the solution, enabling unique CO(2) controllable, efficient in situ recycling of NPs. As compared to non-functionalized AuNPs, t...

Anionic, monolayer-protected gold nanoparticles (AuNPs) have been shown to nondisruptively penetrate cellular membranes. Here, we show that a critical first step in the penetration process is potentially the fusion of such AuNPs with lipid bilayers. Free energy calculations, experiments on unilamellar and multilamellar vesicles, and cell studies all support this hypothesis. Furthermore, we show...

A quantitative colorimetric sensing strategy utilizing cysteamine modified gold nanoparticles (CA-AuNPs) as reporters for Hg(2+) and melamine was demonstrated. Cysteamine is a cheap and commercially available aminothiol and is also the most important chelating ligand in coordination chemistry possessing the ability to coordinate to Hg(2+) and melamine. The terminal thiol group in cysteamine is ...

While the immunogenicity and cytotoxicity of gold nanoparticles (AuNPs) are noted by many researchers, the mechanisms by which AuNPs exert these effects are poorly understood. In this study, we investigated the effects of polyethylene glycolylated AuNPs (PEG@AuNPs) on lipopolysaccharide (LPS)-induced nitric oxide (NO) and interleukin-6 (IL-6) production and the associated molecular mechanism in...

We report here the application of a medicinally important plant Amaranthus spinosus for the synthesis of gold nanoparticles (AuNPs). Different concentrations of ethanolic leaf extract of the plant were reacted with aqueous solution of HAuCl4·4H2O under mild reaction conditions. Synthesis of AuNPs was confirmed from the UV-Vis study of surface plasmon resonance property of the colloidal solution...