Imprinted Polymer Inclusion Membrane Based Potentiometric Sensor for Determination and Quantification of Diethyl Chlorophosphate in Natural Waters

Varada Vishnuvardhan, Yakkala Kalyan, Krishnapillai Padmajakumari Prathish, Battala Gangadhar, Yadamari Tharakeswar, Talasila Prasada Rao, Gurijala Ramakrishna Naidu

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Department of Environmental Sciences, S.V. University, Tirupati – 517 502, India.

DOI: 10.4236/ajac.2011.23046                

Abstract

Biomimetic potentiometric sensor for the determination of diethyl chlorophosphate was developed using im- printed polymer inclusion membrane strategy. Semi-covalent imprinted and non-imprinted polymer particles were synthesized and found that non-imprinted polymer inclusion membrane was unstable in contrast to im- printed polymer inclusion membrane in determination and quantification of diethyl chlorophosphate. Im- printed polymer inclusion membrane based sensor found to be pH dependant with a 5 min equilibrium response time at pH = 10.5 and linearly responds to diethyl chlorophosphate in the concentration range of 1 × 10^–9 to 1 × 10^–4 and 1 × 10^–4 to 1 × 10^–1 mol●L^–9 with a detection limit of 1 × 10^–9 mol●L^–1 (0.17 ppb). It was found that diethyl chlorophosphate response was selective against various selected interferents like pinacolyl methylphosphonate, dimethyl methyl phosphonate, methylphosphonic acid, Phorate and 2, 4-D. The devel- oped sensor was found to be stable for 3 months and can be reusable more than 30 times without loosing sensitivity. The developed sensor was successfully applied for the determination of diethyl chlorophosphate in natural waters.

Keywords

Sensor, Imprinted Polymer Inclusion Membrane, Potentiometry, Diethyl Chlorophosphate, Natural Waters

Conflicts of Interest

The authors declare no conflicts of interest.

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