Molecularly imprinted polymer based potentiometric sensor for the determination of 1-hexyl-3-methylimidazolium cation in aqueous solution

The molecular imprinting technique is powerful to prepare functional materials with molecular recognition properties. In this work, a potentiometric sensor was fabricated by dispersing molecularly imprinted polymers (MIPs) into plasticized PVC matrix and used for the determination of 1-hexyl-3-methylimidazolium cation ([C(6)mim](+)) in aqueous solution. The MIPs were synthesized by precipitation polymerization using 1-hexyl-3-methylimidazolium chloride ([C(6)mim]Cl) as the template molecule, methacrylic acid (MAA) and ethylene glycol dimethacrylat (EGDMA) as the functional monomers, and EGDMA also as the cross-linking agent. The as-prepared electrode exhibited a Nernstian response (58.87 +/- 0.3 mV per decade) to [C(6)mim](+) in a concentration range from 1.0 x 10(-6) to 0.1 mol kg(-1) with a low detection limit of 2.8 x 10(-7) mol kg(-1), high selectivity, and little pH influence. The as-prepared electrode was used for the detection of the [C(6)mim](+) in distilled water, tap water, and river water with a good recovery. It was also successfully applied in the determination of mean activity coefficients of [C(6)mim]Br in fructose + water systems based on the potentiometric method at 298.15 K.