Fluorescent assay based on phenyl-modified g-CN nanosheets for determination of thiram.

Phenyl-modified graphitic carbon nitride nanosheets (Ph-g-CN NSs) were synthesized by a thermal copolymerization and ultrasonic exfoliation method. The Ph-g-CN NSs are used as a fluorescent assay for determination of thiram. The results of X-ray photoelectron spectroscopy, C solid-state nuclear magnetic resonance and Fourier transform infrared spectra confirm that phenyl group is integrated into the heptazine network of g-CN.

A sensitive electrochemical aptasensor for ATP detection based on exonuclease III-assisted signal amplification strategy.

A target-induced structure-switching electrochemical aptasensor for sensitive detection of ATP was successfully constructed which was based on exonuclease III-catalyzed target recycling for signal amplification. With the existence of ATP, methylene blue (MB) labeled hairpin DNA formed G-quadruplex with ATP, which led to conformational changes of the hairpin DNA and created catalytic cleavage sites for exonuclease III (Exo III). Then the structure-switching DNA hybridized with capture DNA which made MB close to electrode surface.