A potentiometric sensor for determination of hydrochinone

Hydroquinone has a high toxicity and therefore its content must be carefully monitored. The development of new easy-to-manufacture electrodes with the best analytical characteristics, which have low cost analysis, is an urgent task. An electrode based on graphite composite material consisting polyurethane (as polymer matrix), powder (to increase electrical conductivity material) 18-molybdodiphosphate reagent) for hydroquinone determination was proposed. advantages polyurethanes modification include adhesion to surface due presence large number polar groups. In addition, specific properties provide physical mechanical polymer. molybdenum heteropoly anion Wales-Dawson type P2Mo18O626- strong enough oxidant. reaction between it some reducing agents almost instantaneous, recovery proceeds without destruction P2Mo18O626-, allows repeated use. Interaction different occurs at acidity solutions. Thus, varying pH solution determining several substances in compatible presence. Fine quantity from 50% 70% added conductivity. amount 20% total weight material. modified synthesized main electrochemical characteristics proposed are determined. Reduction neutral medium (pH 6). response time concentrations 8 min (at temperature 19 °C). This does not "memory effect", relative error 1.3 1.9%, potential deviation range 3-5 mV. limit 2∙10-5 mol/l. effect present evaluated using constant selectivity. selectivity inorganic ions. soaked 3% hydrogen peroxide 10 minutes regeneration.