Functional polymer microspheres as "turn-off" chemosensors for detection of copper cations

Zhang, MM (Zhang, Mengmeng)^{[ 1 ]} ; Si, XW (Si, Xiaowei)^{[ 1 ]} ; Jiang, DH (Jiang, Dehao)^{[ 1 ]} ; Yang, XL (Yang, Xinlin)^{[ 1 ]} ; Lu, Y (Lu, Yan)^{[ 2 ]} ; Shen, YH (Shen, Yinghua)^{[ 3 ]}

COLLOID AND POLYMER SCIENCE 2017, 295(12): 2383-2393

DOI: 10.1007/s00396-017-4209-3

WOS:000414945700012

Abstract

Functional polymer microspheres with fluorescent carbazole unit and various functional groups, such as amide, pyridyl, and imidazole, were prepared by distillation precipitation copolymerization of divinylbenzene (DVB) as a crosslinker, N-vinylcarbazole (NVCz), together with acrylamide (AAm), 4-vinylpyridine (VPy), and 1-vinylimidazole ((VIM) as functional monomers in acetonitrile in the absence of any stabilizer. The resultant polymer microspheres were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), UV-Vis spectroscopy, photoluminescent spectroscopy, inductively coupled plasma (ICP), and X-ray photoelectron microscopy (XPS). The functional polymer microspheres acted as a "turn-off" chemical sensor with excellent stability for determination of copper cation (Cu2+) in methanol via the quenching effect of fluorescence after adsorption of Cu2+ from the solution through the capture ability of functional groups, such as pyridyl, imidazole, and amide on the surface of polymer microspheres. A good linear relationship was set up between the photoluminescence intensity at the emission peak of 352 nm and the Cu2+ concentrations ranging from 0 to 1.0 mu M with the presence of pyridyl group as a ligand. The effects of the functional groups were investigated on the fluorescent response for the microspheres as chemical sensors.