An albumin fluorescent sensor array discriminates ochratoxins.

A sensor array that can distinguish ochratoxins based on the fluorescence of the albumin-ochratoxin complex has been developed. This sensor array enabled the identification of ochratoxins and their mixtures in real food samples.

FRET-Based Host-Guest Supramolecular Probe for On-Site and Broad-Spectrum Detection of Pyrethroids in the Environment.

The massive use of pyrethroid pesticides in agriculture has brought growing concerns about food safety due to their several harmful effects on human health, especially through the accumulation of the food chain. To date, most of the available analytical methods for pyrethroids still suffer from insufficient detection universality, complicated sample pretreatment, and detection processes, which severely limit their practical applications. Herein, a novel Förster resonance energy transfer (FRET)-assisted host-guest supramolecular nanoassembly is reported, for the first time, successfully realizing ratiometric fluorescent detection of pyrethroids in real samples through the indicator displacement assay (IDA) mechanism.

Fast, portable, selective, and ratiometric determination of ochratoxin A (OTA) by a fluorescent supramolecular sensor.

Ochratoxin A (OTA), a mycotoxin found in various food items, possesses significant health risks due to its carcinogenic and toxic properties. Thus, detecting OTA is crucial to ensure food safety. Among the reported analytical methods, there has yet to be one that achieves fast, selective, and portable detection of OTA.

Fast and sensitive detection of nitroxynil using a chalcone-based supramolecular fluorescent sensor.

Nitroxynil as a veterinary drug has been widely used for treatment of parasitic worms in food-producing sheep and cattle. However, the residual nitroxynil in edible animal products can lead to severe adverse effects on human health. Thus, development of an effective analytical tool for nitroxynil is of great significance.

Azocalixarene-Based Supramolecular System for the Detection of Paraquat via an Improved Indicator Displacement Assay.

In view of the lethal toxicity of paraquat (PQ) on human health, herein, a simple indicator displacement assay (IDA) based on an azo-modified calixarene host (azoCX[4]) and a fluorophore guest (-DPD) were elaborately constructed for PQ detection in environmental water samples and plant surfaces. The fluorescent signal of -DPD in the probe can be quenched by azoCX[4] through a photon-induced electron transfer process and recovered upon the addition of PQ within 10 s. The detection range of the -DPD@azoCX[4] probe was calculated to be 0.

Simultaneous determination of glycol ethers and their acetates in cosmetics by gas chromatography with mass spectrometry.

A gas chromatography with mass spectrometry method was developed for the simultaneous determination of ten kinds of glycol ethers and their acetates in cosmetics. The samples were extracted with methanol/ethyl acetate (80:20, v/v), further treated with vortex and ultrasound, and analyzed by gas chromatography with mass spectrometry. The concentration of each analyte was calibrated by the external standard method.

Simultaneous determination of eight alkaloids and oleandrin in herbal cosmetics by dispersive solid-phase extraction coupled with ultra high performance liquid chromatography and tandem mass spectrometry.

We utilized ultra-high performance liquid chromatography with tandem mass spectrometry and dispersive solid-phase extraction to develop a new method for the detection of nine analytes (scopolamine, cephaeline, strychnine, hyoscyamine, brucine, hydrastine, ajmalicine, colchicine, and oleandrin) in herbal cosmetics. Acetonitrile/water and 2-propylaminoethylamine were used to disperse and purify during the dispersive solid-phase extraction step. The analytes were separated by a Waters UPLC HSS T3 column and detected through electrospray ionization source in the positive mode with multi-reaction monitoring conditions.

Simultaneous determination of seven nitrogen-containing phenyl ethers in cosmetics by gas chromatography with mass spectrometry and dispersive solid-phase extraction.

An analytical method was established for the simultaneous determination of seven nitrogen-containing phenyl ethers (2-anisidine, 3-anisidine, 4-anisidine, 2-nitroanisole, 3-nitroanisole, 4-nitroanisole, and 3,3'-dimethoxybenzidine) in cosmetics by gas chromatography with mass spectrometry in this work. The samples were extracted with ethyl acetate and purified with primary secondary amine during the dispersed solid-phase extraction. The analytes were separated by a DB-17MS column and detected in the electron ionization mode of mass spectrometry in the selected ions monitoring mode.

Pd-Porphyrin Oligomers Sensitized for Green-to-Blue Photon Upconversion: The More the Better?

A series of directly meso-meso-linked Pd-porphyrin oligomers (PdDTP-M, PdDTP-D, and PdDTP-T) have been prepared. The absorption region and the light-harvesting ability of the Pd-porphyrin oligomers are broadened and enhanced by increasing the number of Pd-porphyrin units. Triplet-triplet annihilation upconversion (TTA-UC) systems were constructed by utilizing the Pd-porphyrin oligomers as the sensitizer and 9,10-diphenylanthracene (DPA) as the acceptor in deaerated toluene and green-to-blue photon upconversion was observed upon excitation with a 532 nm laser.

Water-soluble triarylboron compound for ATP imaging in vivo using analyte-induced finite aggregation.

Adenosine 5'-triphosphate (ATP) is a multifunctional molecule that participates in many important biological processes. Currently, fluorescence indicators for ATP with high performance are in demand. Reported herein is a novel water-soluble triarylboron compound which displays an apparent ATP-dependent fluorescence enhancement when dispersed in water.

A versatile and robust vesicle based on a photocleavable surfactant for two-photon-tuned release.

A small amphiphile that contains a coumarin unit and alkynyl groups, as a two-photon-cleavable segment and polymerizable groups, respectively, was designed and synthesized. The amphiphile showed a critical aggregation concentration of about 4.6×10(-5)  M and formed a vesicle-type assembly.

Stabilized vesicles consisting of small amphiphiles for stepwise photorelease via UV light.

A small amphiphile consisting of hydrophilic tetraethylene glycol monoacrylate and hydrophobic alkyl chain which were connected by an o-nitrobenzyl unit, a photolabile group, was designed and synthesized. The critical aggregate concentration of the synthesized amphiphile was determined to be about 3 × 10(-5) M by the fluorescence probe technique. Nanosized vesicles were prepared and stabilized by in-situ radical polymerization without altering the morphology.