Colour reaction of phenols with the gibbs reagent. The reaction mechanism and decomposition and stabilisation of the reagent

Effect of Alkaloid-Free and Alkaloid-Rich preparations from Uncaria tomentosa bark on mitotic activity and chromosome morphology evaluated by Allium Test

“…In the case of phenolic compounds, the following mobile phases were used: AcOEt:MeOH:H 2 O:NH 3 (12:3:3:0.5) and isopropanol:MeOH:H 2 O (5:2:3); while for sugar analysis: isopropanol:AcOEt:H 2 O (5:2:3). For staining of phenolic compounds, Gibbs reagent was used, whereas sugars were detected by naphthoresorcine (Stahl and Kaltenbach, 1962;Svobodová et al, 1977).…”

Improvement of the Ammonia Analysis by the Phenate Method in Water and Wastewater

“…20 Investigation on the Gibbs reagent, 2,6-dichloroquinoneimine, revealed that the decomposition of benzoquinon chlorimine was pH dependent; this reagent decomposed completely within 15 min at pH > 10 to form products which do not react with phenol. 21 Although this result was obtained in the absence of nitroprusside catalyst, it gives a hint of the possibility of this kind of side reaction. The unsubstituted chlorimine may decompose even more rapidly as it is more unstable than substituted chlorimine.…”

Biomarkers of urinary tract infections: state of the art, and promising applications for rapid strip-based chemical sensors

“…180 The instability of the BQC is the main limiting factor of the method, which reduces reproducibility and makes qualitative detection the most appropriate application. 181 2. XO catalyzes the formation of superoxides, which subsequently reacts with nitroblue tetrazolium (NBT) to produce formazan dye.…”