DataSheet1_Lable-free aptamer portable colorimetric smartphone for gliadin detection in food.pdf

For individuals with celiac disease (CD), the current clinical therapy option available is a lifelong gluten-free diet. Therefore, it is essential to swiftly and efficiently detect gluten in foods. A colorimetric sensor has been developed, which operates by regulating the aggregation and dispersion state of AuNPs induced by high concentration NaCl through the specific binding of gliadin and aptamer, thereby achieving rapid detection of gliadin in flour. It is found that the sensor exhibits good linearity in the concentration range of 0.67–10 μM and the LOD (3σ/S) is 12 nM. And it can accurately distinguish various types of free-gliadin samples, with a spiked recovery rate of 85%–122.3%. To make the detection process more convenient, the colorimetric results of the biosensor were translated into RGB color-gamut parameters by a smartphone color-picking program for further analysis. Gliadin can still be accurately quantified with the established smartphone platform, and a correlation coefficient of 0.988 was found. The proposed portable smartphone aptamer colorimetric sensing device has achieved satisfactory results in the rapid detection of gliadin in food.</p

Catalytic Synthesis of 2,5-Furandicarboxylic Acid from Furoic Acid: Transformation from C5 Platform to C6 Derivatives in Biomass Utilizations

2,5-Furandicarboxylic acid (2,5-FDCA), a renewable alternative to <i>p</i>-phthalic acid, is the most promising subproduct from 5-hydroxymethylfurfural (HMF). However, HMF is currently synthesized from mono- and polysaccharides like glucose and fructose with limited volume, which apparently blocks the utilization of 2,5-FDCA to replace <i>p</i>-phthalic acid in the polymer industry. Here, we presented a novel route to 2,5-FDCA originating from C5-based furfural which is industrially produced from bulky raw biomaterials, and is not competitive with food for humans. The starting chemical of this synthesis is furoic acid which is currently produced from furfural. Furoic acid can be feasibly transformed to 2,5-FDCA through consecutive bromination, esterification, carbonylation, and hydrolysis with 65% total yield in four steps and above 80% isolated yield in each step. In particular, the key step, palladium-catalyzed carbonylation of ethyl 5-bromo-furan-2-carboxylate, retains 90% isolated yield in the scale-up synthesis. The route introduced here has offered a promising opportunity to access HMF products from furfural derivatives with a large market; meanwhile it offers one of the key C1 resources, that is, CO, a promising utilization in industry

Nonredox Metal-Ion-Accelerated Olefin Isomerization by Palladium(II) Catalysts: Density Functional Theory (DFT) Calculations Supporting the Experimental Data

Redox metal-ion-catalyzed olefin isomerization represents one of the important chemical processes. This work illustrates that nonredox metal ions can sharply accelerate Pd­(II)-catalyzed olefin isomerization, while Pd­(II) alone is very sluggish. Nuclear magnetic resonance (NMR) and ultraviolet–visible light (UV-vis) characterizations disclosed that the acceleration effect originates from the formation of heterobimetallic Pd­(II) species with added nonredox metal ions, which improves the C–H activation capability of the Pd­(II) moiety. Density functional theory (DFT) calculations further confirmed the sharp decrease of the energy barrier in C–H activation by the heterobimetallic Pd­(II)/Al­(III) species