Ultra-sensitive fluorescent biosensor for multiple bacteria detection based on CDs/QDs@ZIF-8 and microfluidic fluidized bed.

An ultra-sensitive fluorescent biosensor based on CDs/QDs@ZIF-8 and microfluidic fluidized bed was developed for rapid and ultra-sensitive detection of multiple target bacteria. The zeolitic imidazolate frameworks (ZIF-8) act as the carrier to encapsulate three kinds of fluorescence signal molecules from the CDs/QDs@ZIF-8 signal amplification system. Besides, three kinds of target pathogenic bacteria were automatically, continuously, and circularly captured by the magnetic nanoparticles (MNPs) in the microfluidic fluidized bed.

An immobilization-free electrochemical biosensor based on CRISPR/Cas13a and FAM-RNA-MB for simultaneous detection of multiple pathogens.

To better respond to biosecurity issues, we need to build good technology and material reserves for pathogenic microorganism screening. Here, we designed an electrochemical/optical signal probe with a common fluorophore and an electrochemically active group, breaking the previous perception that the signal probe is composed of a fluorophore and a quenching group and realizing the response of three signals: electrochemistry, fluorescence, and direct observation. Then, we proposed a homogeneous electrochemical nucleic acid detection system based on CRISPR/Cas named "HELEN-CR" by integrating free electrochemical/optical signal probes and Cas13a cleavage, achieving a limit of detection of 1 pM within 25 min.

Rapid and quantitative detection of Shiga toxin1 and Shiga toxin2 based on multiple targets UPT-LF assay.

Shiga toxin-producing (STEC) infection causes a series of diseases that are highly pathogenic and deadly in humans and animals, seriously endangering public health. Of the pathogenic factors within STEC, the two groups of (Stx) consisting Stx1 and Stx2 plays a prominent role in the pathogenesis of STEC infection. In this study, we developed single-target up-converting phosphor technology-based lateral flow assay (Stx-UPT-LFA) for the rapid detection of Stx1 and Stx2, respectively, and also developed a dual-target Stx1/2-UPT-LFA based on single-target strips to detect of Stx1 and Stx2 at the meantime within 20 min.

No adverse effects of transgenic maize on population dynamics of endophytic Bacillus subtilis strain B916-gfp.

Endophytic bacterial communities play a key role in promoting plant growth and combating plant diseases. However, little is known about their population dynamics in plant tissues and bulk soil, especially in transgenic crops. This study investigated the colonization of transgenic maize harboring the Bacillus thuringiensis (Bt) cry1Ah gene by Bacillus subtilis strain B916-gfp present in plant tissues and soil.

Asymmetric synthesis of 4- and 5-substituted pipecolic esters by ring-closing metathesis and palladium-catalyzed formate reduction.

Asymmetric synthesis of 4- and 5-substituted pipecolic esters was achieved by the sequence of allylation, ring-closing metathesis, and palladium-catalyzed formate reduction.

Regioselective palladium-catalyzed formate reduction of N-heterocyclic allylic acetates.

The regioselective palladium-catalyzed formate reduction of allylic acetates in five- to eight-membered heterocycles is reported. Reduction of allylic acetates under mild conditions using allylpalladium chloride dimer, phosphines, and formic acid/triethylamine in DMF gives the exo-cyclic olefins in good regioselectivities and high yields. Synthetic application in preparing N-tosyl-3-oxo-piperidine is also reported.