Ultrasensitive electrochemical sensor for p-nitrophenyl organophosphates based on ordered mesoporous carbons at low potential without deoxygenization.
p-Nitrophenyl organophosphates (OPs) including paraoxon, parathion and methyl parathion, etc, are highly poisonous OPs, for which sensitive and rapid detection method is most needed. In this work, an ultrasensitive electrochemical sensor for the determination of p-nitrophenyl OPs was developed based on ordered mesoporous carbons (OMCs) modified glassy carbon electrode (GCE) (OMCs/GCE). The electrochemical behavior and reaction mechanism of p-nitrophenyl OPs at OMCs/GCE was elaborated by taking paraoxon as an example. Experimental conditions such as buffer pH, preconcentration potential and time were optimized. By using differential pulse voltammetry, the current response of the sensor at -0.085 V was linear with concentration within 0.01-1.00 μM and 1.00-20 μM paraoxon. Similar linear ranges of 0.015-0.5 μM and 0.5-10 μM were found for parathion, and 0.01-0.5 μM and 0.5-10 μM for methyl parathion. The low limits of detection were evaluated to be 1.9nM for paraoxon, 3.4 nM for parathion and 2.1 nM for methyl parathion (S/N=3). Common interfering species had no interference to the detection of p-nitrophenyl OPs. The sensor can be applicable to real samples measurement. Therefore, a simple, sensitive, reproducible and cost-effective electrochemical sensor was proposed for the fast direct determination of trace p-nitrophenyl OPs at low potential without deoxygenization.
['Zhang|Tingting|T|', 'Zeng|Lingxing|L|', 'Han|Lei|L|', 'Li|Tie|T|', 'Zheng|Cheng|C|', 'Wei|Mingdeng|M|', 'Liu|Aihua|A|']
D002244:Carbon D055664:Electrochemical Techniques D004566:Electrodes D006863:Hydrogen-Ion Concentration D008743:Methyl Parathion D010261:Paraoxon D010278:Parathion D010575:Pesticides D016062:Porosity
Electrochemical sensor p-Nitrophenyl organophosphates Ordered mesoporous carbons Voltammetric detection