Trace-Level Determination of Benzidine and 3,3'-Dichlorobenzidine in Aqueous Environmental Samples by Online Solid-Phase Extraction and Liquid Chromatography with Electrochemical Detection

Abstract

A simple, rapid, and reliable online methodology for the determination of benzidine and 3,3'-dichlorobenzidine (3,3'-DCB) in natural waters is proposed. The analytes are extracted and preconcentrated from aqueous samples in a small stainless steel precolumn packed with a polymeric PLRP-S phase. The precolumn is further online-analyzed by reversed-phase gradient-elution chromatography with a highly sensitive and selective coulometric detection at E = 700 mV. Recoveries greater than 90% and a relative standard deviation of approximately 5% are achieved with samples spiked at low micrograms-per-liter concentration levels. The detection limits of the method in fortified reagent water samples are 100 ng/L for benzidine and 50 ng/L for 3,3'-DCB.

Thiazolylidene‐Catalyzed Cleavage of Methyl Oleate‐Derived α‐Hydroxy Ketone to the Corresponding Free Aldehydes

“…Conventional detection methods for anilines and phenols are liquid or gas chromatography combined with mass spectrometry 5. 6 Immunochemical‐, fluorescence‐, or aptamer‐based analytical approaches have also been recently developed 7.…”

Application of an ampholine-functionalized hybrid organic-inorganic silica material for the SPE of aromatic amines

“…The structure, p K a and log K ow values of these six analytes are shown in Fig. . The reagents for the preparation of ampholine‐functionalized hybrid organic–inorganic silica materials were ampholine (40%, pH 4–6) from Beijing Biodee Biotechnology (Beijing, China), cetyltrimethyl ammonium bromide from Aladdin (Shanghai, China), glutaraldehyde (50%), tetraethyl orthosilicate (98%), and 3‐aminopropyltriethoxysilane (98%) from J&K Scientific (Shanghai, China).…”

Ultra-trace level determinations of benzidine and dichlorobenzidine residues in surface water by liquid chromatography-electrospray ionization tandem mass spectrometry

“…A wide range of analytical techniques has been developed to monitor these contaminants at trace levels in environmental samples. Most of these procedures are based on determining BZ and DCBZ in environmental water by voltammetry [6], gas chromatography with electron capture (GC-ECD) [7], electron-impact (EI) mass spectrometry (MS) [8,9], highperformance liquid chromatography (HPLC) [2,[10][11][12][13][14][15][16][17]. One group used liquid chromatography-tandem mass spectrometry (LC-MS/MS) to identify photodegradation products of BZ and DCBZ, but they did not use that method to determine BZ and DCBZ in water [18].…”