Dual-Gene Isothermal Amplification Coupled with Lateral Flow Strip for On-Site Accurate Detection of in Food Samples.

On-site field detection of in food samples is of utmost importance, since it causes a series of foodborne diseases due to infections-associated ready-to-eat foods. Due to the instrument-free nature, recombinase polymerase amplification (RPA) coupled with lateral flow assay (LFA) is well-suited for such goal. However, the high genomic similarity of different serotypes adds difficulty to accurate differentiation of from others.

Facile monitoring of meat freshness with a self-constructed photosensitization colorimetric instrument.

Total volatile basic nitrogen (TVB-N) produced from the decomposition of amino acids is an important indicator for meat freshness. Various pH-sensitive colorimetric films have been incorporated as intelligent packaging for meat freshness during food transportation. However, methods and instruments capable of on-site end-point detection of meat freshness are still needed for places that provide raw meat without packaging.

Recombinase Polymerase Amplification Coupled with a Photosensitization Colorimetric Assay for Fast spp. Testing.

spp. is one of the most serious foodborne pathogens causing millions of infection cases annually, especially in resource-limited areas. The standard culture method (2-3 days) and current nucleic acid amplification-based testing are not suitable for on-site testing in rural areas with heavy spp.

Phosphorescent inner filter effect-based sensing of xanthine oxidase and its inhibitors with Mn-doped ZnS quantum dots.

Overexpression and crystallization of uric acid have been recognized as the course of hyperuricemia and gout, which is produced via xanthine oxidase (XOD)-catalyzed oxidation of xanthine. Therefore, the medicinal therapy of hyperuricemia and gout is majorly based on the inhibition of the XOD enzymatic pathway. The spectroscopic nature of xanthine and uric acid, namely both absorption (near the ultraviolet region) and emission (non-fluorescent) characteristics, hinders optical assay development for XOD analysis.

Ratiometric Phosphorescent Probe for Thallium in Serum, Water, and Soil Samples Based on Long-Lived, Spectrally Resolved, Mn-Doped ZnSe Quantum Dots and Carbon Dots.

Thallium (Tl) is an extremely toxic heavy metal and exists in very low concentrations in the environment, but its sensing is largely underexplored as compared to its neighboring elements in the periodic table (especially mercury and lead). In this work, we developed a ratiometric phosphorescent nanoprobe for thallium detection based on Mn-doped ZnSe quantum dots (QDs) and water-soluble carbon dots (C-dots). Upon excitation with 360 nm, Mn-doped ZnSe QDs and C-dots can emit long-lived and spectrally resolved phosphorescence at 580 and 440 nm, respectively.

Phosphorescent sensing of Cr3+ with protein-functionalized Mn-doped ZnS quantum dots.

It was found that the phosphorescence from denatured bovine serum albumin (dBSA)-capped Mn-doped ZnS QDs could be selectively quenched by Cr(3+), and a phosphorescent probe for Cr(3+) was thus developed. Based on phosphorescence decay as well as calculations of the relative energies of QDs and Cr(3+), the mechanism for phosphorescent quenching was preliminarily ascribed to electron transfer from photo-excited Mn-doped ZnS QDs to Cr(3+). Under the optimal conditions, good linear Stern-Volmer quenching was obtained for Cr(3+) in the range of 10 to 300 nM.

Interaction between room temperature ionic liquid [bmim]BF4 and DNA investigated by electrochemical micromethod.

Ionic liquids (ILs) as a kind of novel green solvent are being widely used in various researches related to the life sciences and chemistry, which demands the knowledge of interaction between ILs and biomacromolecules. However, the almost completely inert optical, electric, thermal properties of ILs make it difficult to directly obtain information about the interactions. Herein, by using a hydrophilic ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF4) as a model, the electrostatic interaction between ILs and calf thymus DNA (ctDNA) was investigated by a surface electrochemical micromethod.

Flow-focusing generation of monodisperse water droplets wrapped by ionic liquid on microfluidic chips: from plug to sphere.

Generating droplets via microfluidic chips is a promising technology in microanalysis and microsynthesis. To realize room-temperature ionic liquid (IL)-water two-phase studies in microscale, a water-immiscible IL was employed as the continuous phase for the first time to wrap water droplets (either plugs or spheres) on flow-focusing microfluidic chips. The IL, 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]), could wet both hydrophilic and hydrophobic channel surfaces because of its dual role of hydrophilicity/hydrophobicity and extremely high viscosity, thus offering the possibility of wrapping water droplets in totally hydrophilic (THI), moderately hydrophilic (MHI), and hydrophobic (HO) channels.