Comparative studies of neodymium (III)-selective PVC membrane sensors

Abstract

a b s t r a c tSensors based on two neutral ionophores, N,N -bis((1H-pyrrol-2-yl)methylene)cyclohexane-1,2-diamine (L 1 ) and 3,3 -(cyclohexane-1,2-diylbis(azan-1-yl-1-ylidene)bis(methan-1-yl-1-ylidene)bis(5-hydroxymethyl)pyridine-2-ol) (L 2 ) are described for quantification of neodymium (III). Effect of various plasticizers; 2-nitrophenyloctylether (o-NPOE), dibutyl butylphosphonate (DBBP), tri-n-butyl phosphates (TBP), dioctylpthalate (DOP) and chloronapthalen (CN) and anion excluder, sodiumtetraphenylborate (NaTPB) has been studied. The membrane composition of PVC:o-NPOE:ionophore (L 1 ):NaTPB (w/w; mg) of 150:300:5:5 exhibited best performance. The sensor with ionophore (L 1 ) exhibits significantly enhanced selectivity towards neodymium (III) in the concentration range 5.0 × 10 −7 to 1.0 × 10 −2 M with a detection limit of 1.0 × 10 −7 M and a Nernstian compliance (19.8 ± 0.3 mV decade −1 of activity) within pH range 4.0-8.0. The response time of sensor was found as 10 s. The influence of the membrane composition and possible interfering ions has also been investigated on the response properties of the electrode. The fast and stable response, good reproducibility and long-term stability of the sensor are observed. The sensor has been found to work satisfactorily in partially non-aqueous media up to 20% (v/v) content of methanol, ethanol or acetonitrile and could be used for a period of 3 months. The selectivity coefficients determined by using fixed interference method (FIM) indicate high selectivity for neodymium. The proposed electrode shows fairly good discrimination of neodymium (III) from other cations. The application of prepared sensor has been demonstrated in the determination of neodymium (III) in spiked water samples.

Evidence on the 2-nitrophenyl octyl ether (NPOE) facilitating Copper(II) transport through polymer inclusion membranes

“…As a result, the content of PVC increases on the surface of the PIMs after extraction. This assumption is consistent with similar phenomenon in other reports [34,38,[40][41][42].…”

Electrochemically modified sulfisoxazole nanofilm on glassy carbon for determination of cadmium(II) in water samples

“…The obtained surface coverage is 99.96% that is assumed for an intensive and dense film. The standard rate constant, k 0 , can be calculated from equation R ct = RT/(nF) 2 Ak 0 C, where A is the electrode area, n = 1 (electron transfer number of Fe(CN) 6 3−/4− ), C is the concentration of Fe(CN) 6 3−/4− , F is faraday Fig. 5.…”

“…These electrodes are employed for important aims such as metal analysis [1,2], sensor applications [3][4][5][6][7][8][9][10][11][12], drug determination [13][14][15][16] and creating molecular junctions for molecular electronic devices [17,18]. Recently, graphene, a carbon material, and nanoparticles modified electrodes have been prepared and various literatures have been reported for the determination of biological molecules with high sensitivity [19,20].…”

A Novel Potentiometric Sensor Based on 1,2-Bis(N’-benzoylthioureido)benzene and Reduced Graphene Oxide for Determination of Lead (II) Cation in Raw Milk

“…The composition of a membrane plays a very important role in determining the sensitivity and selectivity of an ionophore [41][42][43][44][45]. In order to investigate the effect of composite materials such as PVC matrix, DBP plasticizer, ionophore and sodium tetrakis (4-flurophenyl)borate additive, 9…”