Evaluation of novel Griess-reagent candidates for nitrite sensing in aqueous media identified via molecular fingerprint searching

Abstract

The Griess reaction is the most often exploited colorimetric method for the quantitative analysis of nitrite in aqueous media. The application of the currently used reagents are associated with limitations (e.g. linear response range). Herein, molecular fingerprint searching on well-known Griess-reagents was used as a tool for the identification of structurally similar, new reagent candidate molecules. Rapid and highthroughput experimental evaluation of the newly identified Griess-reagent candidates revealed that 14 of the 18 tested reagent candidates had equal or superior response displaying broader linear ranges and/or increased response gradient against various nitrite concentrations in aqueous media when compared to the parent compounds at room temperature.Scheme 1 Example of a Griess reaction for the detection of nitrite in aqueous media. Fig. 3 Normalised valueswithin the tested parent compounds and candidatesof the width of the linear absorption response range as function of nitrite concentration (black solid bars); and the gradient of the linear regression within this linear range (dashed bars).This journal is

Quantification of Nitrite in Food and Water Samples Using the Griess Assay and Digital Images Acquired Using a Desktop Scanner

“…However, these techniques were expensive. In environmental monitoring and food analysis, the Griess assay has high specificity, selectivity, sensitivity, and accuracy, along with its low-tech requirements, cost-efficiency, and ease of use and it is routinely used and considered as the gold-standard …”

“…In environmental monitoring and food analysis, the Griess assay has high specificity, selectivity, sensitivity, and accuracy, along with its low-tech requirements, cost-efficiency, and ease of use and it is routinely used and considered as the gold-standard. 8 Nowadays, quantitative analyses carried out using digital images obtained with smartphones, desktop scanners, webcams, and digital cameras have been widely applied in chemistry research 9,10 and education 11 to replace the conventional spectrophotometer. Fernandes et al 10 claimed that the popularization of quantitative analysis carried out using digital images resulted in a massive increase in the number of publications related to colorimetric methods.…”

Ultrasensitive Detection of Nitrite through Implementation ofN-(1-Naphthyl)ethylenediamine-Grafted Cellulose into a Paper-Based Device

“…The difference between mobile and immobile indicators, shown in Figure , is the diffuse color obtained via the transportation of the colored product throughout the length of the device with the mobile chromophore (Figure a) in contrast to the darker, localized coloration of the detection zone with the immobile indicator (Figure b). Of the two reactive components necessary for nitrite detection, N -(1-naphthyl)­ethylenediamine was chosen as the molecule to graft to the cellulose because sulfanilamide and nitrite react first to form a diazonium salt before the reaction with N -(1-naphthyl)­ethylenediamine can occur. While immobilization of both indicators was considered, additional difficulties would arise from such a design, including those from the protection and deprotection of sulfanilamide required for functionalization.…”

“…The Griess reaction typically utilizes two indicators, sulfanilamide and N -(1-naphthyl)­ethylenediamine (NED), which, in the presence of nitrite, form a highly colored azo dye (Scheme ). Sulfanilamide first reacts with nitrite to form a diazonium salt intermediate, which rapidly undergoes a nucleophilic aromatic substitution with N -(1-naphthyl)­ethylenediamine to produce the azo dye . While similar reagents can, and have been, be used, , these reagents are commonly regarded as the optimal choices.…”

“… Sulfanilamide first reacts with nitrite to form a diazonium salt intermediate, which rapidly undergoes a nucleophilic aromatic substitution with N -(1-naphthyl)­ethylenediamine to produce the azo dye . While similar reagents can, and have been, be used, , these reagents are commonly regarded as the optimal choices. N -(1-Naphthyl)­ethylenediamine is the most sensitive, rapid, and pH tolerant of the known potential candidates, and sulfanilamide reacts rapidly with N -(1-naphthyl)­ethylenediamine and nitrite to produce a stable colored product within seconds .…”