Limit of Quantitation (LOQ) of Arsenic

The application gives the method for determination of the LOQ for arsenic (As³⁺) by potentiometric and voltametric determination using   the DMi140-SC combined platinum ring redox electrode, and the DM143-SC platinum double pin sensor, respectively.

Background:

Arsenic (As) is considered as one of the most toxic element because of its adverse physiological effect on human health.

Arsenic can exist in four valence states i.e. -3, 0, +3 and +5, The +3 valency is the dominant form under reducing conditions such as in presence of mineral acids. Arsenic ions present in trivalent state (+3 valency) are best determined by titration method where it has been oxidized to +5 valency using Iodine.

One of the most relevant parameter in analytical chemistry is the Limit of Quantification (LOQ). The term LOQ describes the lowest concentration of the analyte that produces quantitative measurements with acceptable precision and accuracy. In this application note, the LOQ for arsenic (As³⁺) is determined by potentiometric and voltametric indication using both electrodes.

This application note includes:

• Introduction
• Sample Preparation and Procedures
• Solutions and Chemicals
• Chemistry
• Instruments and Accessories
• Method in Detail
• Results and Remarks

And method files (.lmt and .xml) for direct import and implementation on the instrument.