Study of a Novel Bisnaphthalimidopropyl Polyamine as Electroactive Material for Perchlorate-selective Potentiometric Sensors

• Published in: Electroanalysis (New York, N.Y.) Vol. 27; no. 12; pp. 2809 - 2819
• Main Authors: Gil, Renato, Amorim, Célia G., Crombie, Laura, Kong Thoo Lin, Paul, Araújo, Alberto, da Conceição Montenegro, Maria
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 01.12.2015; WILEY‐VCH Verlag
• Subjects: Bisnaphthalimidopropyl polyamine; Membranes; perchlorate; Perchlorates; Phenyls; Plasticizers; Polyamines; Polyvinyl chlorides; potentiometry; Sensors; Slopes; waters
• ISSN: 1040-0397; 1521-4109
• DOI: 10.1002/elan.201500275

In this work, the new polyamine bisnaphthalimidopropyl‐4,4’‐diaminodiphenylmethane is proposed as a new ionophore for perchlorate potentiometric sensors. The optimal formulation for the membrane comprised of 12 mmol kg−1 of the ionophore, and 68 % (w/w) of 2‐nitrophenyl phenyl ether as plasticizer and 31 % (w/w) of high molecular weight PVC. The sensors were soaked in water for a week to allow leakage of anionic impurities and for one day in a perchlorate solution (10−4 mol L−1) to improve reproducibility due to its first usage. The stability constant for the ionophore‐perchlorate association in the membrane, log βIL1=3.18±0.04, ensured a performance characterized by the slope of 54.1 (±0.7) mV dec−1 to perchlorate solutions with concentrations between 1.24×10−7 and 1.00×10−3 mol L−1. The sensors are insensitive to pH between 3.5 to 11.0, they have a practical detection limit of 7.66 (±0.42) ×10−8 mol L−1 and a response time below 60 s for solutions with perchlorate concentrations above 5×10−6 mol L−1. The accuracy of the results was confirmed by the analysis of the contaminant in a certified reference water sample.