"Dual Signal-On" Split-Type Aptasensor for TNF-α: Integrating MQDs/ZIF-8@ZnO NR Arrays with MB-Liposome-Mediated Signal Amplification.

Ultrasensitive and accurate detection of biomarkers in serum is of great importance for disease diagnosis and treatment. So far, the commonly used single-mode signal suffers from certain instinct drawbacks that restrict assay performances. Herein, we report the proof-of-concept fabrication of a split-type photoelectrochemical (PEC) and electrochemical (EC) dual-modal aptasensor for ultrasensitively tracing tumor necrosis factor-α, a noteworthy biological biomarker with essential clinical importance. By smart integrating molybdenum disulfide QDs/zeolitic imidazolate framework-8@ZnO nanorod arrays with a methylene blue-liposome-mediated signal amplification strategy, "dual signal-on" detection is accomplished based on a sandwich reaction of the target with aptamer-anchored carboxyl magnetic beads and an aptamer-confined MB liposome. Linear ranges of 5 fg/mL-5 µg/mL (detection limit 1.46 fg/mL) for PEC and 10 fg/mL-0.5 µg/mL (detection limit 6.14 fg/mL) for EC are obtained, respectively. An independent signal transduction mechanism supports the accuracy improvement, and a separate biological process from a translator enables convenient fabrication, short-time consumption, wider linearity, as well as outstanding reproducibility and stability in practical application. This work presents a universal bioassay route with prospects in biomedical and related areas.

A New Family of Photoluminescent Polymers with Dual Chromophores.

A new family of photoluminescent polymers with dual chromophores is prepared in this study by using poly(maleic anhydride-alt-vinyl acetate), acetone, and metal hydroxide. These polymers, which contain both bulky carboxylic ester groups and metal carboxylate groups, are found to be dual-emission photoluminescent, with a blue luminescence excitation-dependent group and a red luminescence excitation-independent group. These photoluminescence polymers with a nonconjugated structure and dual chromophores also show characteristics of aggregation-induced emission (AIE). The luminous intensities of the AIE fibers prepared using the polymers are found to increase after stretching, in contrast to traditional photoluminescent fibers with the aggregation-caused quenching property. The study also finds that the stretched fibers can emit the three primary colors when irradiated by ultraviolet, blue, and green light.

Water-Soluble Polymers with Strong Photoluminescence through an Eco-Friendly and Low-Cost Route.

Photoluminescence (PL) of nonconjugated polymers brings a favorable opportunity for low-cost and nontoxic luminescent materials, while most of them still exhibit relatively weak emission. Strong PL from poly[(maleic anhydride)-alt-(vinyl acetate)] (PMV) from low-cost monomer has been found in organic solvents, yet the necessity of noxious solvents would hinder its practical applications. Herein, through a novel, eco-friendly, and one-step route, PMV-derived PL polymers can be fabricated with the highest quantum yield of 87% among water-soluble nonconjugated PL polymers ever reported. These PMV-derived polymers emit strong blue emission in both solutions and solids, and can be transformed into red-emission agents easily. These PL polymers exhibit application potentials in light-conversion agricultural films. It is assumed that this work not only puts forward a convenient preparation routine for nonconjugated polymers with high PL, but also provides an industrial application possibility for them.

Electrochemical reduction and flow detection of iodate on (Bu4N)2Mo6O19 self-assembled monolayer.

A stable monolayer of the inorganic-organic hybrid polyoxometalate (Bu4N)2Mo6O19, denoted as Mo6O19, was formed on a sodium-3-mercapto-1-propanesulfonate (MPPS)-covered gold electrode surface, interlaced with an anionic poly(dimethyldiallylammonium chloride) (PDDA) binding layer based on the electrostatic self-assembled (ESA) technique. Electrochemical characterization of the Mo6O19 self-assembled thin films on the solid surface by cyclic voltammetry and AC impedance spectroscopy revealed a stable and sensitive electrocatalytic response to the reduction of iodate. Iodate was determined amperometrically through a flow injection cell at the modified electrode in the concentration range of 1.0 x 10(-6) to 1.0 x 10(-1) M with a detection limit of 8 x 10(-8) M (signal-to-noise ratio = 3). Performance was improved to meet practical needs compared with previously reported analogues.