Novel neodymium(III) membrane sensor based on N-(2-furylmethylene)pyridine-2,6-diamine

We found that N-(2-furylmethylene) pyridine-2,6-diamine (FPD) can be used as an excellent ionophore in the construction of a novel neodymium(III) poly(vinyl chloride) (PVC)-based membrane sensor. A membrane composition of 33% poly (vinyl chloride), 59% nitrobenzene (NB), 6% FPD, and 2% potassium tetrakis (p-chlorophenyl) borate (KTpClPB), led to the optimum results. The Nd(III)-selectivity of the sensor, is relatively good in comparison to a large number of lanthanide metal ions, such as lanthanum, cerium, gadolinium, samarium, terbium, europium, dysprosium, and ytterbium ions. The sensor response is Nernstian (with slope of 19.6 +/- 0.3 mV per decade for the triply charged ion) over a wide concentration range (1.0 x 10(-5) to 1.0 x 10(-2) mol L-1) with a detection limit of 7.0 x 10(-6) mol L-1, a relatively fast response time, in the whole concentration range (< 15 s), and a considerable life time of at least six weeks in the pH range of 4.0-8.0.