Quantification of organic contaminants in urban stormwater by isotope dilution and liquid chromatography-tandem mass spectrometry was written by Hou, Fan;Tian, Zhenyu;Peter, Katherine T.;Wu, Christopher;Gipe, Alex D.;Zhao, Haoqi;Alegria, Ernesto A.;Liu, Fengmao;Kolodziej, Edward P.. And the article was included in Analytical and Bioanalytical Chemistry in 2019.Formula: C13H24N2O This article mentions the following:
Pollutants transported in urban stormwater runoff induce pervasive water quality degradation in receiving waters. To accurately characterize stormwater quality and treatment system performance across the range of possible contaminant characteristics, comprehensive multi-residue anal. methods are necessary. Here, we developed a solid-phase extraction (SPE) and high-performance liquid chromatog.-tandem mass spectrometry (HPLC-MS/MS) method to quantify representative stormwater-derived organic contaminants across multiple chem. classes, including vehicle-related chems., corrosion inhibitors, industrial chems., pesticides, pharmaceuticals and personal care products, and antioxidants. Extraction conditions, isotope-labeled internal standards, and LC-MS/MS parameters were optimized to enhance recovery, minimize matrix effects, and maximize selectivity and sensitivity. The developed method was sensitive (method quantification limits < 10 ng/L for > 80% of selected analytes) and accurate (mean relative recoveries in the range of 70-130%, with relative standard deviations < 25% for 77% of the analytes) for most of the analytes. The method was used to analyze samples collected from nine urban watersheds during a storm event; 62% of the 39 analytes were detected at least once at concentrations up to 540 ng/L (1,3-diphenylguanidine). Spatial trends in detection and concentration were observed for vehicle-related and industrial chems. that correlated with vehicle traffic. Total concentrations of pesticides suggested that residential uses could be more important sources than agriculture. This study illustrates the pervasive occurrence of a wide variety of stormwater-derived chems. in urban receiving waters and highlights the need to better understand their environmental fate and ecol. implications. [Figure not available: see fulltext.]. In the experiment, the researchers used many compounds, for example, 1,3-Dicyclohexylurea (cas: 2387-23-7Formula: C13H24N2O).
1,3-Dicyclohexylurea (cas: 2387-23-7) belongs to amides. The solubilities of amides and esters are roughly comparable. Typically amides are less soluble than comparable amines and carboxylic acids since these compounds can both donate and accept hydrogen bonds. Tertiary amides, with the important exception of N,N-dimethylformamide, exhibit low solubility in water. The presence of the amide group –C(=O)N– is generally easily established, at least in small molecules. It can be distinguished from nitro and cyano groups in IR spectra. Amides exhibit a moderately intense νCO band near 1650 cm−1. By 1H NMR spectroscopy, CONHR signals occur at low fields. In X-ray crystallography, the C(=O)N center together with the three immediately adjacent atoms characteristically define a plane.Formula: C13H24N2O
Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics