Triplex DNA-based aggregation-induced emission probe: A new platform for hybridization chain reaction-based fluorescence sensing assay.

The hybridization chain reaction (HCR), as one of the nucleic acid amplification technologies, is combined with fluorescence signal output with excellent sensitivity, simplicity, and stability. However, current HCR-based fluorescence sensing methods still have some defects such as the blocking effect of the HCR combination with fluorophores and the aggregation-caused quenching (ACQ) phenomenon of traditional fluorophores. Herein, a triplex DNA-based aggregation-induced emission probe (AIE-P) was designed as the fluorescent signal transduction, which is able to provide a new platform for HCR-based sensing assay.

A visual detection strategy for SARS-CoV-2 based on dual targets-triggering DNA walker.

SARS-CoV-2, a highly transmissible and mutagenic virus, made huge threats to global public health. The detection strategies, which are free from testing site requirements, and the reagents and instruments are portable, are vital for early screening and play a significant role in curbing the spread. This work proposed a silver-coated glass slide (SCGS)/DNA walker based on a dual targets-triggering mechanism, enzyme-catalyzed amplification, and smartphone data analysis, which build a portable visual detection strategy for the SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) gene.

Label-free fluorescent aptasensor for chloramphenicol based on hybridization chain reaction amplification and G-quadruplex/-methyl mesoporphyrin IX complexation.

The use of the broad-spectrum antibiotic chloramphenicol (CAP) in food is strictly regulated or banned in many countries. Herein, for the sensitive, rapid, and specific detection of CAP in milk, a label-free fluorescence strategy was established based on guanine (G)-quadruplex/-methyl mesoporphyrin IX (NMM) complex formation and hybridization chain reaction (HCR) amplification. In this system, CAP can specifically bind to an aptamer (Apt) to release an Apt-C sequence from double-stranded DNA (Apt·Apt-C).