Simultaneous Electrochemical Detection of Co-Existing Dihydroxybenzene Isomers Using Porphyrin Zr Metal-Organic Frameworks/β-cyclodextrin/Pencil Graphite Electrode

An inexpensive and eco-friendly electrochemical sensor based on PCN-224/
$\beta $
-CD/PPGE nanocomposite is presented to simultaneously detect hydroquinone (HQ), catechol (CC) and resorcinol (RS), the common pollutants in life environment. PPGE is an ordinary pretreated active pencil lead used as base electrode. On the surface of PPGE electrode,
$\beta $
-CD and PCN-224 synergistically play the role to achieve simultaneous detection of HQ, CC, RS. On one hand,
$\beta $
-CD could selectively form host-guest inclusion complexes with targets, and on the other hand the combination of PCN-224 could help to build higher surface area and enhance the recognition to HQ, CC, RS. The characterization of PCN-224/
$\beta $
-CD/PPGE was performed by fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM). Under the optimal conditions, the proposed sensor exhibited excellent electrochemical performance with corresponding limits of detection of
$0.07 ~\mu \text{M}$
,
$0.12 ~\mu \text{M}$
and
$0.41 ~\mu \text{M}$
(S/N = 3) and a same linear concentration ranges of 1-
$750 ~\mu \text{M}$
for HQ, CC and RS respectively. Additionally, PCN-224/
$\beta $
-CD/PPGE sensor has good reproducibility, stability and selectivity. It is evaluated to has reliability and potential practicality according to the recovery rate results in Lake water and Yangtze River water and the results compared with which obtained by high performance liquid chromatography (HPLC).