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Rationale: The Chemical Weapons Convention (CWC) mandates rigorous screening of chemical weapons and their potential degradation/reaction products, which is essential to identify such products in suspected samples. The reaction between 2‐(N,N‐dialkylamino)ethylchlorides and 2‐(N,N‐dialkylamino)ethanols (precursors/degradation products of VX agents) produces a new class of reaction products that are not explored. Methods: The reaction products, bis(2‐N,N‐dialkylaminoethyl)ethers (1–10), were synthesized using established synthetic procedures, and gas chromatography/mass spectrometry (GC/MS) (electron ionization [EI] and chemical ionization [CI]) methods were developed for their identification. The GC/MS experiments were performed on an Agilent GC/MSD system using an HP‐5MS capillary column. Methane gas was used as the CI reagent gas for GC/CIMS experiments. GC/retention index (RI) values of 1–10 were calculated using the retention times of the hydrocarbon mixture and the analytes. Results: The GC/EI spectra of 1–10 exhibited [M‐H]+ ions and distinctive fragments that provided valuable structural information. The selective fragmentation of the alkyl groups on nitrogen facilitated the discrimination of possible isomeric compounds. Interpretation of EI fragments in the high mass region is important for unambiguous identification of 1–10, because the major ions significantly match other CWC‐related compounds containing the 2‐(N,N‐dialkylaminoethyl) group. GC/CI (methane) spectra included M+., [M + H]+, [M‐H]+, reagent‐specific adduct ions, and a few structure‐indicative fragments. The spiking experiments in soil and water samples revealed that the target analytes were stable, easily extractable, and detectable using GC/MS. Conclusions: The reaction products, 1–10, could be successfully synthesized and characterized using GC/MS (EI and CI). The GC/MS and GC/RI data provide important insights into the unambiguous identification of the target molecules in challenging CWC verification and are helpful in participation in the Organization for the Prohibition of Chemical Weapons proficiency tests. [ABSTRACT FROM AUTHOR]

End-stage renal disease (ESRD) is a rapidly increasing health problem, and every year, about 2 million ESRD cases are reported worldwide. Hemodialysis (HD) is the vital renal reinstatement therapy for ESRD, and HD patterns play a crucial role in patients' health. Plasma metabolomics is the potential approach to understanding the HD process, effectiveness, and patterns. The lack of protein vitality is a primary problem for HD patients, and the quantities of amino acids intracellularly and in the blood are considered to be a symbolic index of protein metabolism and nutrition conditions. In the current study, LC/MS/MS and GC/MS methods were developed for 29 targeted plasma metabolites and validated as per ICH bioanalytical method validation M10 guidelines. The 29 metabolites included 20 proteinogenic amino acids and nine other related metabolites. The methods were employed to measure the absolute quantities (µM) of the targeted metabolites in HD patients (n=60) before and after dialysis (PRE-HD and POST-HD), and compared with the healthy control (HC) group (n=60). Phenylacetylglutamine was found to be higher in both PRE-HD (72.88±14.5 µM) and POST-HD (26.62±7.9 µM), when compared to HC (1.61±0.6 µM). On the other hand, glutamic acid was lower in PRE-HD (14.90±6.5 µM), and POST-HD (13.6±6.1 µM) than that of HC (245.4±37.8 µM). The dialytic loss was found to be 52–45% for arginine, lysine, and histidine, while it was 38–26% for glycine, cysteine, proline, alanine, threonine, glutamine, valine, and methionine. The dialytic loss was low (≤12%) for aspartic acid, glutamic acid, asparagine, leucine, tyrosine, tryptophan, and isoleucine. Graphical abstract adapted from mass spectrometry templates by Biorender.com retrieved from https://app.biorender.com/biorender-templates. [ABSTRACT FROM AUTHOR]