Ninhydrin-based spectrophotometric assays of trace cyanide

Abstract

Abstract:The extreme toxicity of cyanide, its wide industrial application as well as its continued illegal use generate research interest in different fields of science, imposing multidisciplinary approach to study cyanide poisoning. We show here that the reaction between cyanide and ninhydrin can be performed at ambient conditions; however, the ninhydrin reagent has to be freshly prepared in oxygen free solvent. Besides, we show that the reading of the absorbance at 485 nm might be more suitable and reliable than that at 590 nm, where the pH-dependent blue colored cyanide-ninhydrin adduct is less stable. Ninhydrin-based color reagent can be used to quantify the cyanide released from plant seeds. In sodium carbonate medium, the proposed assay is fast, cheap and environmentally friendly.

Conversion of cassava leaf to bioavailable, high‐protein yeast cell biomass

“…Dry cassava leaves were Wiley milled to 40 mesh and analyzed for ash, total water and ethanol soluble contents, structural sugars, acids and acid‐insoluble lignin following published protocols . The cyanogen content of cassava leaves was assayed following published protocols with small modifications . Briefly, milled cassava leaves (10 mg) were extracted in 5 mL of 0.1% sodium bicarbonate with sonication in a water bath.…”

“…[21][22][23] The cyanogen content of cassava leaves was assayed following published protocols with small modifications. 24 Briefly, milled cassava leaves (10 mg) were extracted in 5 mL of 0.1% sodium bicarbonate with sonication in a water bath. The supernatant (100 μL) was combined with 50 μL of 5 mg mL −1 ninhydrin in argon-purged 2% sodium carbonate and reacted for 15 min.…”

Quantitative Estimation of Hydrogen Cyanide in Fresh and Cooked Tuber Parenchyma (Pulp) of Three Cultivars of Sweet Cassava Cultivars Grown in Some Parts of Benue State, Nigeria

“…The cyanide level in cassava samples was determined according to the method described by Surleva et al [12]. A calibration graph was first constructed where standard solutions of CN − at concentrations of 0.02, 0.04, 0.08, 0.1 and 0.2 μg/mL (which is within the linear range) were prepared by adding appropriate volumes of cyanide solutions at concentration of 20 μg CN − /mL to 1 mL of 2% Na 2 CO 3 .…”

“…The samples were sonicated for 20 min in a water bath. 1 mL of the mixture measured by use of automatic pipette was centrifuged at 10000 rpm for 10 minutes and two aliquots of supernatant (2 mL each) were taken for spectrophotometric analysis [12].…”

Determination of Cyanide Content in Three Sweet Cassava Cultivars in Three Local Government Areas of Benue State, Nigeria

“…The cyanide concentration in cassava parenchyma was determined using ninhydrin based spectrometer of trace cyanide at 485 nm maximum wavelength [26]. A calibration graph was first constructed using standard solutions of CN − at concentrations of 0.02, 0.04, 0.08, 0.1 and 0.2 μg/mL (which is within the linear range) and was prepared by adding appropriate volumes of cyanide solutions at concentration of 20 μg CN − /mL to 1 mL of 2% Na 2 CO 3 .…”