Cyanide Determination With a Modified Ninhydrin Reagent Using N-Acetyl Cysteine in the Presence of Heavy Metal Ions

Abstract

Sensitive and selective, but fast and simple assays of cyanide ion in waste and natural waters, as well as in biological samples are required in case of accidental pollution with such species. Cyanide reaction with ninhydrin has been recommended for instant detection of small traces of cyanide (detection limit 1.5 ng ml -1 ). However, the oxidizers and heavy metal ions, such as Hg, Cu, Ag may interfere with the determinations. Therefore, we report here cyanide determination with ninhydrin and its usage in monitoring polluted water with heavy metals. The effect of heavy metals and SH-compounds were studied in order to increase the method range of use. N-acetyl cysteine proved to be a selective reagent for protection of cyanide detection and determination against the interference of heavy metal ions.

Colorimetric Approaches To Drug Analysis And Applications – A Review

“… Cyanide: 0.5 mL of ninhydrin reagent is added to cyanide and potassium hydroxide solution that gave deep-red (485 nm) or deep-blue color (590 nm) 36 .…”

Analisis Tiosianat Dalam Urin Sebagai Metode Monitoring Potensi Gaki (Gangguan Akibat Kekurangan Iodium) Berbasis Test Kit

“…Analisis sianida juga dapat dilakukan berdasarkan pembentuk an kompleks hidrin-dantin antara sianida dengan ninhidrin. Hidrindantin dapat membentuk 2-siano-1,2,3-trihidroksi-2hidrindatin dengan siani-da yang lain (Mihaescu, 2010 …”

A Study on Ninhydrin Reaction with Weak Acid Dissociable Cyanide and Its Application for Toxic Cyanide Determination

“…Ninhydrin-cyanide reaction was proved to be strongly interfered by mercury (II), cooper (II) and silver (I), and at less extent by Ni 2+ , Zn 2+ and Cd 2+ [16,17]. However, a possible implementation of ninhydrin reagent for complex cyanide determination was supposed based on following facts: (1) cyanide bounded in complexes with Hg(II); Cu(I) and Ag(I) is 2-4 times more than the metal ion and respectively the equilibrium concentration of cyanide is higher than metal ion concentration; (2) in cooper-cyanide complex Cu(I) is involved and its reaction with ninhydrin has not been studied; (3) two competing reactions could be supposed metal-ninhydrin and cyanide-ninhydrin and difference in the reaction rates could be explored.…”

“…Cysteine, thiourea and tetraethylenepentamine were chosen as they were reported to give complete recovery in different combinations with sulfur or amine based ligands for on-line gas-diffusion flow-injection determination of WAD cyanide [11,14]. Moreover, it was described that cysteine did not interfere with ninhydrin-cyanide reaction, but quantitative data were not provided [17]. This report presents the results from a study on the ninhydrin-WAD cyanide reaction in the presence of ligand exchange reagents without separation of liberated cyanide ions.…”