Related Experiment Video
Updated: Jul 12, 2026

Integration of Miniaturized Solid Phase Extraction and LC-MS/MS Detection of 3-Nitrotyrosine in Human Urine for Clinical Applications
Published on: July 14, 2017
Determination of urinary homovanillic acid using the nitrosonaphthol reaction
Abstract:
Determination of urinary homovanillic acid (HVA) is an important analysis to establish the diagnosis and prognosis of neuroblastoma. A method is presented for the determination of this metabolite of dopamine using its reaction with 1-nitroso-2-naphthol and nitrous acid. The method has shown a sensitivity, specificity, positive predictive value, negative predictive value, and efficiency of 100%, 97.4%, 92.3%, 100%, and 98%, respectively. In the last two years, four new cases of neuroblastoma have been diagnosed, with the use of this method, one of which has no increase in the concentration of urinary vanillylmandelic acid.
More Related Videos
07:38A General Method for Detecting Nitrosamide Formation in the In Vitro Metabolism of Nitrosamines by Cytochrome P450s
Published on: September 25, 2017
08:23Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds
Published on: February 16, 2022
Related Concept Videos
Electrophilic Aromatic Substitution: Nitration of Benzene
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Overview
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by water loss...
2° Amines to N-Nitrosamines: Reaction with NaNO2
Amines to Sulfonamides: The Hinsberg Test
Generally, a primary amine reacts with the Hinsberg reagent to produce an N-substituted benzenesulfonamide. The electron-withdrawing sulfonyl...
Urine Studies I: Urinalysis
Urine Studies II: Urine Culture and Sensitivity Test