Influence of Multiwalled Carbon Paste Nanotubes on Response of ${\rm Pb}^{2+}$ Ion Selective Carbon Paste Electrode Based on 2-((6-(5-Bromo-2-Hydroxybenzylideneamino) Hexylim

A new lead selective carbon paste electrode by incorporation of 2-((6-(5-bromo-2-hydroxybenzylideneamino) hexylimino) methyl)-4-bromophenol (BHBAHMBP) as new carrier in matrix of carbon paste has been reported. Influence of amount of carbon paste ingredints including sodium tetraphenylborate (NaTPB), BHBAHMBP, Nujol, graphite powder, amount of Multiwalled carbon nanotubes optimized and their value was set as carbon: (500/3.4/150/6.0/50 mg), respectively. At optimum values of variables these conditions the proposed electrode response toward Pb²⁺ ion was linear in the range of 5.0×10^-7 to 1.0×10^-1 mol L^-1 with slope of 29.50 mV per decade^-1 of Pb²⁺ ion concentration and detection limit of 2.5×10^-7 mol L^-1. The electrode response is independent of pH in the range of 2.7-4.0, while the response time of the electrode was ~ 40 s. The potentiometric selectivity coefficients and selectivity sequence of proposed Pb²⁺ ion selective electrode has been evaluated using fixed interference method (FIM). The electrode successfully has been applied for potentiometric determination of pb²⁺ ion content in various real samples and as indicator electrode in precipitation titration.