Fabrication of Pb2+ Ion Selective Electrode Based on 1-((3-((2-Hydroxynaphthalen-1-yl)Methyleneamino)-2,2-Dimethylpropylimino) Methyl) Naphthalen-2-ol as New Neutral Ionophore

Abstract

The potentiometric investigation of complexation of 1 - ((3 - ((2 – hydroxynaphthalen – 1 – y l) methyleneamino) – 2, 2 – dimethylpropylimino) methyl) naphthalen-2-ol (HMDMN) show strong interaction between HMDMN and Pb2+ ion while their formation constant was evaluated using potentiometric data. The suitability of the HMDMN for construction of new Pb2+ ion PVC membrane electrode and its potentiometric determination was investigated. The influence of variables including pH, membrane ingredients was optimized and set as PVC: DBP: carrier: NaTPB: NaTPB /carrier mole ratio with the percent mass ratio of 28.9:57.8: 8.0: 5.33: 0.83. At optimum values of all variables the electrode response is linear in the concentration range of 1.0×10−6 to 0.1 M with detection limit 4.0×10−7 M with nernstian slop of 25.79 mV/decade over the pH range of 5.0-7.2. This electrode with appropriate response time about 10s and suitable reproducibility (RSD), can be used for a at least 2 month without any measurable divergence in response properties. The proposed sensor reveals good selectivity toward pb2+ ion with respect to many alkali, alkaline earth, transition and heavy metal ions. It was applied to the determination of pb2+ in water and soil samples.