Iron oxide nanoparticles adsorb fluorescently labeled DNA oligonucleotides via the backbone phosphate and quench fluorescence. Arsenate displaces adsorbed DNA to increase fluorescence, allowing detection of arsenate down to 300 nM. This is a new way of using DNA: analyte recognition relies on its phosphate instead of the bases.

Arsenic, one of the most toxic and dangerous elements in the environment affecting millions of people around the world, is associated with several diseases. In this pilot study, we investigated removal of arsenate from aqueous solutions using chitosan under the influences of initial arsenic ion concentrations, pH, contact time, and adsorbent dosages of chitosan. In order to assess the sorption ...

Polymeric beads functionalised with a chemical receptor show they can remove arsenate from contaminated water to levels below 5 ppb (well the WHO guideline value of 10 ppb).

Phytoplankton plays an important role in arsenic speciation, distribution, and cycling in freshwater environments. Little information, however, is available on arsenic efflux from the cyanobacteria Microcystis aeruginosa under different phosphate regimes. This study investigated M. aeruginosa arsenic efflux and speciation by pre-exposing it to 10 µM arsenate or arsenite for 24 h during limited ...

Kinetic data indicate that rabbit muscle glyceraldehyde d-phosphate dehydrogenase possesses two types of diphosphopyridine nucleotide-binding sites. The actual chemical reaction (oxidation-reduction) occurs at tight sites. Binding of DPN to loose sites activates the reaction at the tight sites. These results are consistent with the concept that the enzyme is “double headed,” with oxidation-redu...

Geobacillus kaustophilus strain A1 was previously isolated from a geothermal environment for its ability to grow in the presence of high arsenate levels. In this study, the molecular mechanisms of arsenate resistance of the strain were investigated. As(V) was reduced to As(III), as shown by HPLC analysis. Consistent with the observation that the micro-organism is not capable of anaerobic growth...

Although arsenic is a trace element in terms of its natural abundance, it nonetheless has a common presence within the earth's crust. Because it is classified as a group VB element in the periodic table, it shares many chemical and biochemical properties in common with its neighbors phosphorus and nitrogen. Indeed, in the case of this element's most oxidized (+5) oxidation state, arsenate [HAsO...

This study investigated arsenate and arsenite adsorption on an iron(III) oxide/silica adsorbent that had a Fe/Si molar ratio of 3. Batch experiments were conducted with regard to adsorption kinetics, isotherms, pH effects and interference of phosphate and sulfate on arsenic adsorption. The adsorption of arsenite was faster than that of arsenate. The adsorption kinetics could be well described b...

A radioisotope method was devised to study bacterial respiratory reduction of arsenate in sediments. The following two arsenic-rich soda lakes in California were chosen for comparison on the basis of their different salinities: Mono Lake (approximately 90 g/liter) and Searles Lake (approximately 340 g/liter). Profiles of arsenate reduction and sulfate reduction were constructed for both lakes. ...

Accumulation of arsenic in plant tissues poses a substantial threat to global crop yields. The use growth-promoting bacterial strains mitigate heavy metal toxicity has been illustrated before. However, its potential reduce uptake and not investigated date. Here, we describe the identification characterization Nocardiopsis lucentensis strain isolated from contaminated soil. Inoculation with this...