A rapid and reliable liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous confirmation of 13 sulfonamides in honey was developed and fully validated in accordance with the European Commission Decision No 2002/657/EC. The validation scheme was built in accordance with the target level of 50μgkg(-1) for all analytes. The sulfonamides investigated were as follows: sulfaguanidine (SGN), sulfanilamide (SNL), sulfadiazine (SDZ), sulfathiazole (STZ), sulfamerazine (SMR), sulfamethizole (SMZ), sulfadimerazine (SDM), sulfamonomethoxine (SMNM), sulfamethoxypiridazine (SMP), sulfadoxine (SDX), sulfamethoxazole (SMX), sulfaquinoxaline (SQX) and sulfadimethoxine (SDT). Several extraction procedures were investigated during the development phase. Finally, the best results were obtained with a procedure using acidic hydrolysis and cation exchange purification. Chromatographic separation was achieved on a C18 analytical column. Matrix effects were also investigated. Data acquisition implemented for the confirmatory purpose was performed by monitoring 2 MRM transitions per analyte under the positive electrospray mode. Mean relative recoveries ranged from 85.8% to 110.2% and relative standard deviations lying between 2.6% and 19.8% in intra-laboratory reproducibility conditions. The decision limits (CCα) ranged from 1.8 to 15.5μgkg(-1). High resolution mass spectrometry was used to investigate the possible formation of sulfonamide metabolites in honey. The validation results proved that the method is suitable for the screening and confirmatory steps as implemented for the French monitoring residue plan for sulfonamides residue control in honeybees.
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http://dx.doi.org/10.1016/j.chroma.2014.03.003 | DOI Listing |
Electrophoresis
January 2025
Institute for Infectious Diseases, University of Bern, Bern, Switzerland.
Computer simulation was utilized to characterize the electrophoretic processes occurring during the enantioselective capillary electrophoresis-mass spectrometry (CE-MS) analysis of ketamine, norketamine, and hydroxynorketamine in a system with partial filling of the capillary with 19 mM (equals 5%) of highly sulfated γ-cyclodextrin (HS-γ-CD) and analyte detection on the cathodic side. Provided that the sample is applied without or with a small amount of the chiral selector, analytes become quickly focused and separated in the thereby formed HS-γ-CD gradient at the cathodic end of the sample compartment. This gradient broadens with time, remains stationary, and gradually reduces its span from the lower side due to diffusion such that analytes with high affinity to the anionic selector become released onto the other side of the focusing gradient where anionic migration and defocusing occur concomitantly.
View Article and Find Full Text PDFBMC Biol
January 2025
Department of Agricultural Sciences, University of Naples Federico II, Naples, Italy.
Background: Deformed wing virus (DWV) is a major honey bee pathogen that is actively transmitted by the parasitic mite Varroa destructor and plays a primary role in Apis mellifera winter colony losses. Despite intense investigation on this pollinator, which has a unique environmental and economic importance, the mechanisms underlying the molecular interactions between DWV and honey bees are still poorly understood. Here, we report on a group of honey bee proteins, identified by mass spectrometry, that specifically co-immunoprecipitate with DWV virus particles.
View Article and Find Full Text PDFJ Biomed Sci
January 2025
Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, State Key Laboratory of Anti-Infective Drug Discovery and Development, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510006, China.
Background: Recent studies indicate that N6-methyladenosine (mA) RNA modification may regulate ferroptosis in cancer cells, while its molecular mechanisms require further investigation.
Methods: Liquid Chromatography-Tandem Mass Spectrometry (HPLC/MS/MS) was used to detect changes in mA levels in cells. Transmission electron microscopy and flow cytometry were used to detect mitochondrial reactive oxygen species (ROS).
Angew Chem Int Ed Engl
January 2025
Xiamen University, Department of Chemistry, CHINA.
A pyrrole-fused analogue of warped nanographene, designated as deca-nitrogen doped 'WNG' (azaWNG), was synthesized through the annular fusion of decapyrroylcorannulene. The resulting azaWNG exhibited extremely limited solubility in common organic solvents and was characterized solely by mass spectrometry. Theoretical calculations revealed that azaWNG has a sunflower-like molecular structure with electron-deficient corannulene as the core and electron-rich pyrrole as the petals, demonstrating a significantly narrower energy gap compared to all-carbon WNG.
View Article and Find Full Text PDFArch Bronconeumol
January 2025
Department of Allergy and Clinical Immunology, Department of Respiratory and Critical Care Medicine, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, National Center for Respiratory Medicine, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, China; Guangzhou National Laboratory, Guangzhou, Guangdong, China. Electronic address:
Objectives: To investigate the microbiota and metabolome of patients with ABO compared with bronchiectasis and asthma, and determine the relevance with clinical characteristics, inflammatory endotype and exacerbation risks.
Methods: In this prospective cohort study, patients underwent comprehensive assessments, including sputum differential cell count, and sputum collection at baseline. Sputum microbiota was profiled via 16S rRNA gene sequencing and metabolome via liquid chromatography/mass spectrometry.
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