Compound-specific isotope analysis of benzotriazole and its derivatives

Abstract

Compound-specific isotope analysis (CSIA) is an important tool for the identification of contaminant sources and transformation pathways, but it is rarely applied to emerging aquatic micropollutants owing to a series of instrumental challenges. Using four different benzotriazole corrosion inhibitors and its derivatives as examples, we obtained evidence that formation of organometallic complexes of benzotriazoles with parts of the instrumentation impedes isotope analysis. Therefore, we propose two strategies for accurate δ 13 C and δ 15 N measurements of polar organic micropollutants by gas chromatography isotope ratio mass spectrometry (GC/IRMS). Our first approach avoids metallic components and uses a Ni/Pt reactor for benzotriazole combustion while the second is based on the coupling of online methylation to the established GC/IRMS setup. Method detection limits for on-column injection of benzotriazole, as well as its 1-CH 3 -, 4-CH 3 -, and 5-CH 3 -substituted species were 0.1-0.3 mM and 0.1-1.0 mM for δ 13 C and δ 15 N analysis respectively, corresponding to injected masses of 0.7-1.8 nmol C and 0.4-3.0 nmol N,

The relative influence of derivatization and normalization procedures on the compound‐specific stable isotope analysis of nitrogen in amino acids

“…Instrumentation effects, including combustion reactor composition and condition, [47,48] can have significant effects on the combustion efficiencies of different molecules. [47,[49][50][51][52] Heteroatoms, such as the nitrogen found in the ring structures of the heterocyclic amino acids (His, Pro, pyroGlu, Trp), have been found to affect combustion during GC/C/IRMS, [47,52,53] as have components of the incorporated derivatization reagents. [9,15,31] Therefore, the derivatization technique may also interact with combustion to affect δ 15 N measurements.…”

Solid-phase extraction method for stable isotope analysis of pesticides from large volume environmental water samples

“…35 Carbon and nitrogen CSIA of ATR, ACETO, METO, DEA and BAM in ethyl acetate (EtAc) was performed by GC/IRMS according to modified methods. 19,23,30,60 Carbon CSIA of DPC in water was performed by LC/IRMS as explained elsewhere. 35 For measuring N isotope signatures of DPC, derivatization with trimethylsilyldiazomethane was performed prior to GC/IRMS analysis.…”

Hydrophilic trace organic contaminants in urban stormwater: occurrence, toxicological relevance, and the need to enhance green stormwater infrastructure

“…New analytical techniques such as compound-specific isotope analysis (CSIA) may be applied to identify predominant sources of relevant chemicals and develop elimination strategies. 214 • Increasing evidence suggests that separate storm sewers can be impacted by raw sewage leading to discharge of elevated levels of hyphil-TrOCs and other pollutants. Little is known about the input pathways and the nationwide extent of storm sewer cross-contamination with wastewater.…”