posted on 2016-10-05, 00:00authored byZhiyi Yao, Yadong Qiao, Haiqin Liang, Wenqi Ge, Li Zhang, Zhong Cao, Hai-Chen Wu
We
have developed a unique approach for enhancing the sensitivity
of pyrenyl probes based on polyelectrolyte-induced nanoassemblies
and explored its sensing application toward 2,4,6-trinitrophenol (TNP).
The key issue of the method is the formation of the nanoassemblies
which possess high-density charges, specific surface area, and inner
hydrophobic regions. These properties would help increase the loading
of analytes and promote probe–analyte interactions, thereby
leading to the prominent enhancement of the sensitivity. In the course
of TNP detection, pyrene nanoassemblies can bind TNP efficiently through
cooperative noncovalent interactions including electrostatic, π–π
stacking, and charge-transfer interactions, resulting in the distinct
fluorescent responses of pyrene moieties. This system has excellent
selectivity and sensitivity for TNP detection. The detection limit
is as low as 5 nM. It may be used for monitoring the TNP concentrations
in real-world samples.