Neutral red retention time assay in determination of toxicity of nanoparticles.

The neutral red retention time (NRRT) assay is useful for detecting decreased lysosomal membrane stability in haemocytes sampled from bivalves, a phenomenon often associated with exposure to environmental pollutants including nanomaterials. Bivalves are popular sentinel species in ecotoxicology and use of NRRT in study of species in the genus Mytilus is widespread in environmental monitoring. The NRRT assay has been used as an in vivo test for toxicity of carbon nanoparticles (Moore MN, Readman JAJ, Readman JW, Lowe DM, Frickers PE, Beesley A.

Luminescent optical detection of volatile electron deficient compounds by conjugated polymer nanofibers.

Optical detection of volatile electron deficient analytes via fluorescence quenching is demonstrated using ca. 200 nm diameter template-synthesized polyfluorene nanofibers as nanoscale detection elements. Observed trends in analyte quenching effectiveness suggest that, in addition to energetic factors, analyte vapor pressure and polymer/analyte solubility play an important role in the emission quenching process.

Germanium nanocrystals as luminescent probes for rapid, sensitive and label-free detection of Fe3+ ions.

Luminescent water-soluble germanium nanocrystals (Ge NCs) have been developed as a fluorescent sensing platform for the highly selective and sensitive detection of Fe3+ via quenching of their strong blue luminescence, without the need for analyte-specific labelling groups. The amine-terminated Ge NCs were separated into two discrete size fractions with average diameters of 3.9±0.

Proteomic evaluation of citrate-coated silver nanoparticles toxicity in Daphnia magna.

Recent decades have seen a strong increase in the promise and uses of nanotechnology. This is correlated with their growing release in the environment and there is concern that nanomaterials may endanger ecosystems. Silver nanoparticles (AgNPs) have some of the most varied applications, making their release into the environment unavoidable.

Size controlled synthesis of silicon nanocrystals using cationic surfactant templates.

Alkyl-terminated silicon nanocrystals (Si NCs) are synthesized at room temperature by hydride reduction of silicon tetrachloride (SiCl₄) within inverse micelles. Highly monodisperse Si nanocrystals with average diameters ranging from 2 to 6 nm are produced by variation of the cationic quaternary ammonium salts used to form the inverse micelles. Transmission electron microscopy imaging shows that the NCs are highly crystalline, while FTIR spectra confirm that the NCs are passivated by covalent attachment of alkanes, with minimal surface oxidation.

Gold nanoparticles and oxidative stress in the blue mussel, Mytilus edulis.

Relatively little is known about how gold nanoparticles (GNP) might interact in vivo with aquatic organisms. Gold nanoparticles (GNP) of defined average diameter may be synthesized and used to challenge test organisms held in aquaria. The blue mussel, Mytilus edulis, is a popular sentinel species in environmental toxicology.

Oxidative stress and toxicity of gold nanoparticles in Mytilus edulis.

Gold nanoparticles (AuNP) have potential applications in drug delivery, cancer diagnosis and therapy, food industry and environment remediation. However, little is known about their potential toxicity or fate in the environment. Mytilus edulis was exposed in tanks to 750 ppb AuNP (average diameter 5.

Exposure of the blue mussel, Mytilus edulis, to gold nanoparticles and the pro-oxidant menadione.

Relatively little is known about how gold nanoparticles (GNP) might interact in vivo with marine organisms. Mytilus edulis was exposed (24h) to approximately 15 nm GNP, menadione and both compounds simultaneously (GNP/menadione). GNP was detected by inductively coupled plasma-optical emission spectroscopy mainly in digestive gland of samples exposed to GNP though not GNP/menadione, perhaps due to impaired feeding.

A potential and ion switched molecular photonic logic gate.

A molecular photonic logic gate is demonstrated by integrating electrical (potential) and chemical (ionic) switching functions into molecules attached at an externally addressable semiconductor substrate.

Effect of base stacking on the relative thermodynamic stability of oligonucleotide complexes: a spectroscopic study.

Three-strand oligonucleotide complexes are employed to assess the effect of base stacking and base pair mismatch on the relative thermodynamic stabilities of oligonucleotide duplexes. The melting behavior of three-strand oligonucleotide complexes incorporating nicks and gaps as well as internal single base mismatches is monitored using temperature-dependent optical absorption spectroscopy. A sequential three-state equilibrium model is used to analyze the measured melting profiles and evaluate thermodynamic parameters associated with dissociation of the complexes.