PVC Membrane Selective Electrode for Determination of Isoproterenol based on Naphthylethylenediamine Dihydrochloride–Tetraphenyl Boranuide

A new coated–wire membrane selective electrode as a potentiometric sensor was developed for the determination of isoproterenol. Naphthylethylenediamine dihydrochloride–tetraphenyl boranuide ion–exchangers was used as an electroactive material on the membrane. The sensor displays a linear response with a slope of 56.9 mV decade–1 for isoproterenol in the concentration range of 1.0×10–2–5.0×10–6 mol L–1, with detection limit of 3.3×10–6 mol L–1. The potentiometric response is independent of the pH of the solution in the pH range of 3.0 – 6.8. Selectivity coefficient data for some common inorganic cations, sugars and components of the mixed drugs were investigated and showed negligible interference. The response time of <5 s was displayed. The sensor can be used for more than 2 months without any considerable divergence in the potential. For the practical purposes, the efficiency of the method in the extraction and determination of isoproterenol for biological fluids such as urine and blood serum samples was evaluated without any special pretreatment.