Capillary Isoelectric Focusing of Proteins and Peptides Using an In-Line cIEF-ESI Interface with Improved MS Characteristics.

Intact protein analysis using mass spectrometry (MS) is an important technique to characterize and provide a comprehensive overview of protein complexity. It is also the basis of "top-down" approaches in proteomics to describe the proteoforms of single protein's post-translational modifications (PTMs). MS-based analysis of intact proteins benefits from high-resolution separations prior to electrospray ionization.

Drug survival analysis of etanercept compared with monoclonal antibody tumour necrosis factor-α inhibitors in rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis: a propensity score-matched analysis from the Czech ATTRA registry.

Objectives: To compare the drug survival of etanercept to monoclonal tumour necrosis factor-α inhibitors in rheumatoid arthritis, ankylosing spondylitis and psoriatic arthritis.

Methods: Patients initiating first line biological therapy with tumour necrosis factor-α were propensity score matched and compared for drug survival with a Kaplan-Meier analysis.

Results: We matched 657 to 657 patients in rheumatoid arthritis, the median survival time on etanercept was 44.

Comprehensive Lipidomic Automation Workflow using Large Language Models.

Lipidomics generates large data that makes manual annotation and interpretation challenging. Lipid chemical and structural diversity with structural isomers further complicates annotation. Although, several commercial and open-source software for targeted lipid identification exists, it lacks automated method generation workflows and integration with statistical and bioinformatics tools.

Lipid Isobar and Isomer Imaging Using Nanospray Desorption Electrospray Ionization Combined with Triple Quadrupole Mass Spectrometry.

Mass spectrometry imaging (MSI) is widely used for examining the spatial distributions of molecules in biological samples. Conventional MSI approaches, in which molecules extracted from the sample are distinguished based on their mass-to-charge ratio, cannot distinguish between isomeric species and some closely spaced isobars. To facilitate isobar separation, MSI is typically performed using high-resolution mass spectrometers.

Digital Quadrupole Isolation and Electron Capture Dissociation on an Extended Mass Range Q-TOF Provides Sequence and Structure Information on Proteins and Protein Complexes.

Electron capture dissociation (ECD) is now a well-established method for sequencing peptides and performing top-down analysis on proteins of less than 30 kDa, and there is growing interest in using this approach for studies of larger proteins and protein complexes. Although much progress on ECD has been made over the past few decades, establishing methods for obtaining informative spectra still poses a significant challenge. Here we describe how digital quadrupole (DigiQ) ion isolation can be used for the mass selection of single charge states of proteins and protein complexes prior to undergoing ECD and/or charge reduction.