Sub ppb detection levels for Total Cyanide analysis on the San++ Continuous Flow Analyzer

The implementation of a new type of flow cell  in the San++ has already been used to increase the sensitivity for the automated procedure of Total Phosphate and Total Phenol considerably, but is now also available for the analysis of Total Cyanide. Extremely low concentrations of Total Cyanide in all kinds of aqueous samples can be measured. This increased sensitivity is achieved due to the flow cell having an optical path length of 50 cm.

Skalar’s procedure for Total Cyanide analysis is in accordance with  ISO 14403-2:2012 (distillation or gas dialysis) determination of Total Cyanide. The photometric determination is based on the reaction of cyanide with chloramine-T under the formation of cyanogen chloride. This reacts with 4-pyridine carboxylic acid and 1,3- dimethylbarbituric acid to give a red color, which is measured at 600 nm.

Note: The detection limits of this procedure also comply to the ranges mentioned in the Environmental Quality Standards for Water Framework Directive by United Kingdom Technical Advisory Group, Annex VIII substances: cyanide.

Typical performance data and analysis results of Skalar’s Total Cyanide application on the San++ analyzer using the new type of flow cell can be found in the table and graphs below.

Application performance:

San++ analysis data Total Cyanide
Ranges 0.02 - 20 µg/L
Minimum Detection Limit (MDL) 0.01790 µg/l
RSD (%) 0.003%
Regression (r) 0.9999












Total Cyanide calibration curve (0.02 - 20 µg CN/L)









Calibration line results for the range up to 20 μg/L








Total Cyanide calibration (0.02- 20 µg/L)

Besides the above Skalar has more solutions for automatic analysis of different cyanide species such as free cyanide, weak acid dissociable cyanide and thiocyanide available. All cyanide applications are according to EPA or ISO methodologies. Please contact Skalar for the possibilities.