Electrochemical recognition of nitrophenol isomers by assembly of pillar[5]arenes mutifilms

Xiaoping Tan; Genfu Zhao; Xu Zhou; Taohong Li; Hong Lei; Guanben Du; Long Yang

doi:10.1016/j.aca.2018.06.085

Electrochemical recognition of nitrophenol isomers by assembly of pillar[5]arenes mutifilms

Anal Chim Acta. 2018 Dec 7:1036:49-57. doi: 10.1016/j.aca.2018.06.085. Epub 2018 Jul 3.

Authors

Xiaoping Tan¹, Genfu Zhao², Xu Zhou², Taohong Li², Hong Lei², Guanben Du², Long Yang³

Affiliations

¹ Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Yunnan Province Key Lab of Wood Adhesives and Glued Products, School of Materials Science and Engineering, Southwest Forestry University, Kunming, 650224, China; Key Lab of Inorganic Special Functional Materials, Chongqing Municipal Education Commission, School of Chemistry and Chemical Engineering, Yangtze Normal University, Chongqing, 408100, China.
² Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Yunnan Province Key Lab of Wood Adhesives and Glued Products, School of Materials Science and Engineering, Southwest Forestry University, Kunming, 650224, China.
³ Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Yunnan Province Key Lab of Wood Adhesives and Glued Products, School of Materials Science and Engineering, Southwest Forestry University, Kunming, 650224, China; Key Lab of Inorganic Special Functional Materials, Chongqing Municipal Education Commission, School of Chemistry and Chemical Engineering, Yangtze Normal University, Chongqing, 408100, China. Electronic address: long133109070@126.com.

PMID: 30253836
DOI: 10.1016/j.aca.2018.06.085

Abstract

The rational design of electrochemical methods for isomer recognition is a focus of research in the molecular recognition and separation fields. In this work, a novel, rapid, and convenient electrochemical approach for recognition of nitrophenol isomers was constructed based on the alternating layer-by-layer (LbL) assembly of water-soluble cationic and anionic pillar [5]arene on a carboxylic graphene (C-Gra) modified glass carbon electrode. The electrochemical recognition of nitrophenol isomers was investigated by differential pulse voltammetry (DPV). The electrochemical results reveal that both the peak currents of m-nitrophenol (m-NP) and p-nitrophenol (p-NP) increased with the increasing of the layer number of the assembled pillar [5]arene, whereas the peak current of o-nitrophenol (o-NP) decreased with the increased layers, which demonstrated an efficient route for discriminating the nitrophenol isomers. The molecular recognition mechanism was studied by ¹H NMR spectra, which indicated that the m-NP and p-NP can be included in the cavity of the pillar [5]arene host. However, the o-NP could not enter into the host of pillar [5]arene, which was ascribed to the formation of intramolecular hydrogen bond of o-NP. The LbL assembly modified GCE was used for detecting p-NP and m-NP. A low detection limit of 0.33 μM (S/N = 3) and a linear response range of 1-90 μM for p-NP were obtained by using this method. And the detection limit of 0.16 μM (S/N = 3) and a linear response range of 0.5-70 μM for m-NP were obtained. This method of LbL assembly modified GCE has potential application in molecular recognition and separation.

Keywords: Electrochemical recognition; Layer-by-layer assembly; Nitrophenol isomers; pillar[5]arene.