Indirectly Determination of Urea Using Chloride Ion Selective Electrode after its Extraction and Preconcentration by Molecularly Imprinted Polymer

A molecularly imprinted polymer material having urea molecule selective cavities was prepared. It was shown that the MIP had a considerable selectivity for urea in comparison to similar compounds such as thiourea. The obtained polymer was used as an adsorber for solid phase extraction (SPE) of urea from aqueous samples. The polymer containing urea was then washed with water/ethanol mixture and subsequently it was contacted with free chorine solution. Cl- ions, produced by reaction of hypochlorite and urea, was determined via a Cl- selective electrode. Some different parameters of SPE were optimized and the developed procedure was used for urea determination in real sample.