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

Abstract

Biomimetic potentiometric sensor for the determination of diethyl chlorophosphate was developed using imprinted 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 imprinted polymer inclusion membrane in determination and quantification of diethyl chlorophosphate. Imprinted 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 -2 mol·L -1 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 developed 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.

Conductance based sensing and analysis of soluble phosphates in wastewater

“…Figures 4 to 6 depict the mean change in conductance, from just before adding the test solution (at t=0), until a period six minutes after the addition of the test sample. The change in membrane conductivity can be attributed to conformational changes in the polymer upon template binding, which together with the presence of charged ions in the polymer matrix lead to a consequent increase in conductivity of the membrane (Piletsky et al, 1995;Sergeyeva et al, 1999;Suedee et al, 2006 andVishnuvardhan et al, 2011).…”

“…However, it is interesting to note that other MIP based sensors have been used repeatedly with no loss of sensitivity. A potentiometric sensor used a MIP based membrane to measure the concentration of diethyl chlorophosphate in ground and river water and was reused over thirty times with reproducible results (Vishnuvardhan et al, 2011). Additionally, a flow through conductometric sensor used a MIP based receptor for the on-line measurement of haloacetic acids, with no loss of performance after more than fifty repeat measurements (Suedee et al, 2006).…”

“…MIP based sensors have been integrated with a range of electrochemical transducers (Piletsky and Turner, 2002). A number of MIP based sensors have used conductance based transduction methods, induced by conformational changes in the cavity produced when a MIP's receptor elements have bound their specific target (Piletsky et al, 1995;Sergeyeva et al, 1999;Suedee et al, 2006 andVishnuvardhan et al, 2011). Furthermore, conductance measurements are relatively easy to perform, are already used in environmental monitoring and applicable for continuous measurement in wastewater treatment works (Levlin, 2010).…”

Imprinted nanospheres based on precipitation polymerization for the simultaneous extraction of six urinary benzene metabolites from urine followed by injector port silylation and gas chromatography-tandem mass spectrometric analysis

“…due to their high binding affinity and high stability at harsh conditions. These materials has reusability of 30-80 extractions without losing recognition abilities and found to be thermailly stable [27]. Various methods like bulk polymerization, precipitation polymerization, suspension polymerization, multi-step polymerization were used during the synthesis of MIPs [28].…”

Molecularly Imprinted Polymers (MIP) Based Electrochemical Sensor for Detection of Endosulfan Pesticide

“…The molecular imprinting technique continues to be a fascinating field of analytical chemistry offering strategies for creating molecule-specific recognition matrices with recognition capabilities analogous to those of biological receptors [10]. The positions, shape, and size of the functional groups in the sites of recognition generated are complementary to its original analyte.…”