Construction, characteristics and application of a benzene-1,2,4-tricarboxylic acid selective electrode

Abstract

Liquid and poly(vinyl chloride) membrane electrodes that are highly selective and sensitive to benzene-1,2,4-tricarboxylic acid (trimellitic acid) were developed. Both electrodes exhibit a linear response in the range 10^–1–10^–5M over the pH range 6–9 with a near-Nernstian slope of 27–28 mV per concentration decade at 25 °C. As little as 1 mg ml^–1 of trimellitic acid can be measured directly with an average recovery of 98.7%(standard deviation 1.8%) and without interference from many organic acids and inorganic anions.