Chitosan-stabilized gold nanoparticles decorated with a thiodiacetic acid nanoprobe for selective detection of arsenic(iii) in rice and water samples.

A sensitive and selective method for the detection of arsenic(iii) (As) based on chitosan-stabilized gold nanoparticles (CS/AuNPs) decorated with a 2,2'-thiodiacetic acid (TDA) nanoprobe was developed and used to detect and indicate the contamination of rice, drinking water and environmental water samples. AuNPs were reduced and stabilized with CS and subsequently functionalized with TDA. As interacted with the carboxylate group of TDA to form an As-TDA complex, inducing the aggregation of CS/AuNPs@TDA.

A novel magnetite C18/paracetamol/alginate adsorbent bead for simultaneous extraction of synthetic antioxidants and bisphenol A in water samples.

A novel magnetic composite bead was synthesized using carbon 18, paracetamol and alginate (mC18/Pa/Alg). The bead was applied to simultaneously adsorb butylated hydroxytoluene, butylated hydroxyanisole, and bisphenol A from water samples by magnetic solid-phase extraction (MSPE). The adsorbed analytes were determined by gas chromatography-flame ionization detection.

Highly specific colorimetric detection based on aggregation of l-cysteine functionalized gold nanoparticles for cypermethrin in water samples.

A fast, simple, and selective colorimetric assay for quantifying cypermethrin in water samples is proposed using l-cysteine functionalized gold nanoparticles (AuNPs@Cyst). Cypermethrin is hydrolyzed by potassium hydroxide to obtain hydrolyzed cypermethrin in the form of 3-phenoxybenzaldehyde by-product (HCy). The detection strategy is based on the aggregation of AuNPs@Cyst caused by hydrogen-bonding recognition between the aldehyde group of HCy and the amine group of l-cysteine on the surface of AuNPs@Cyst.

A novel double metal-dithizone functionalized polyurethane electrospun nanofiber and film for colorimetric determination of hexavalent chromium.

This work proposes a highly specific method of Cr determination based on the double reactions of two metals, Co with dithizone to form a (DTZ)-Co complex, and the replacement of Co in the formed complex with Cr. The fast degradation of DTZ in solution in wet analysis was overcome by preparing dithizone functionalized polyurethane nanofibers that were electrospun into a membrane (DTZ/PU-NF) and a microwell plate film (DTZ/PU-MPF). For comparison, the performance of diphenylcarbazide (DPC), a currently used complexing agent for Cr, was also investigated.

Lattice dynamic stability and electronic structures of ternary hydrides La Y H first-principles cluster expansion.

Lanthanum hydride compounds LaH become stabilized by yttrium substitution under the influence of moderate pressure. Novel materials with a wide range of changes in the structural properties as a function of hydrogen are investigated by means of the first-principles cluster expansion technique. Herein, the new compounds La Y H, where 0 ≤ ≤ 1, are determined to adopt tetragonal structures under high-pressure with the compositions LaYH, LaYH, and LaYH.

Highly sensitive colorimetric sensing of copper(ii) ions based on "CLICK-17" DNAzyme-catalyzed azide modified gold nanoparticles and alkyne capped dsDNA cycloaddition.

A click chemistry assay based on a newly discovered DNAzyme, CLICK-17, with azide modified gold nanoparticles (azide-AuNPs) and alkyne capped dsDNA (alkyne-linker DNA) was employed for novel and selective detection of Cu visually. The strategy involved using CLICK-17 to mediate a catalytic reaction for triazole formation between azide-AuNPs and alkyne-linker DNA under the help of Cu (without sodium ascorbate) or Cu, which eventually led to the aggregation of AuNPs. The obvious color change from ruby red to bluish purple was then observed by the naked eye and the absorbance peak shifted from 525 to 570 nm.

Robust colorimetric detection based on the anti-aggregation of gold nanoparticles for bromide in rice samples.

Inorganic bromide (Br) is an important contaminant ion as it can originate from the overuse of illegal methyl bromide as a fumigant in stored rice samples. Herein, we developed a simple and highly sensitive colorimetric sensor for bromide ion detection in rice samples. The sensor is based on the anti-aggregation of gold nanoparticles (AuNPs) by Br in the presence of Cr, which made the method more selective than other typical aggregations of nanoparticles.