Fabrication of an Amperometric Sensor for Hydroxylamine Based on Silver Paste Nanocomposite Electrode

Electrocatalytic oxidation of hydroxylamine (NH₂OH) was investigated at silver (Ag) paste nanocomposite electrode. This electrode is a very good alternative for hydroxylamine determination compared with previously described electrodes because the electrocatalytic effect was achieved without any electrode modification. NH₂OH was determined over a wide linear concentration range of 1.0 μM-5.0 mM with double potential step amperometry. The limit of detection was obtained as 0.3 μM. This new method of NH₂OH determination is reproducible, selective, sensitive, and can be used for real sample analysis. The independence of the system from most of the interferences is the other advantageous feature of this sensor.

I. Introduction

Hydroxylamine is known as a kind of reducing agent. It has been identified as a key intermediate in the microbial processes of the nitrogen cycles. These processes are nitrification and anaerobic ammonium oxidation [1].