Amperometric Environmental Phosphate Sensors

We report a novel amperometric sensor for aqueous phosphate ions in freshwater systems based on the reductive square wave voltammetry of molybdate(VI) anions immobilized within a chitosan matrix deposited on a glassy carbon electrode. A sensitivity of 4.4 +/- 0.1 mu A/mu M was realized together with a LOD of 0.15 mu M. The sensor was insensitive to chloride and nitrate ions below a threshold concentration of 1.0 mM. Analytical measurements were successfully made in authentic samples of tap and pond water.

Automated summary

A novel amperometric sensor for aqueous phosphate ions in freshwater systems was developed utilizing reductive square wave voltammetry of molybdate(VI) anions immobilized within a chitosan matrix. The sensor exhibited high sensitivity and low LOD, and demonstrated stability in the presence of chloride and nitrate ions at low concentrations. Analytical measurements were successfully conducted in authentic samples of tap and pond water.