Luminescent AuNPs@Tb/adenosine monophosphate nanostructures for 2,6-pyridinedicarboxylic acid detection

Abstract

Luminescent nanoscale coordination polymers (NCPs) have been found to have promising potential application in sensing. Herein, novel luminescent Au nanoparticles (AuNPs)@Tb/adenosine monophosphate (AMP) NCP nanostructures were prepared by encapsulating AMP-functionalized AuNPs into Tb/AMP NCPs for the detection of 2,6-pyridinedicarboxylic acid (DPA). The as-prepared AuNPs@Tb/AMP NCP nanostructures were characterized by transmission electron microscopy, UV-vis absorbance spectroscopy, dynamic light scattering and luminescence spectroscopy. The results showed that the AuNPs@Tb/AMP NCP nanostructures were very stable in aqueous solutions. The coordination of DPA with Tb³⁺ in the AuNPs@Tb/AMP NCP nanostructures by replacing the water molecules to form AuNPs@Tb/AMP NCPs–DPA caused intermolecular energy transfer from DPA to Tb³⁺, leading to the enhancement of the AuNPs@Tb/AMP NCP luminescence. The obtained AuNPs@Tb/AMP NCP nanostructures as a probe for the detection of DPA demonstrated high sensitivity and selectivity with a good linear range (10 nM to 10 μM) and a low detection limit (2.7 nM) which was well below the anthrax infectious dose.