Goal
To demonstrate an automated, chromatography-free, microflow electrospray ionization–mass spectrometry (ESI-MS) workflow for rapid and reproducible analysis of peptide digests, denatured intact monoclonal antibodies (mAbs), and native mAbs using the UniDirect platform and Newomics M3 multinozzle emitters.
Introduction
Modern high-resolution mass spectrometers offer rapid data acquisition, but chromatographic separation, equilibration, and sample handling can limit overall analytical throughput. Direct-infusion electrospray ionization mass spectrometry (ESI-MS) provides a complementary approach for rapid sample analysis when chromatographic separation is not required [1–2]. However, routine high-throughput operation requires reliable sample introduction, stable ionization, synchronized MS acquisition, and effective washing between samples.
Previous studies have established the advantages of multinozzle electrospray technology [3–6] and demonstrated its applications in top-down proteomics, native mass spectrometry, antibody characterization, and other biopharmaceutical analyses [7–13]. Building on this foundation, UniDirect™ integrates automated sample introduction with Newomics M3 multinozzle electrospray technology, synchronized MS acquisition, and automated washing. By distributing the sample flow across multiple spray nozzles, the M3 emitter enables stable electrospray ionization and efficient analysis of peptide digests, intact proteins, and native proteins and their complexes without liquid chromatography.
This application note presents experimental results obtained using a UniDirect™ platform coupled to a Thermo Scientific Q Exactive Plus mass spectrometer. The results demonstrate the capabilities of UniDirect for rapid, automated, high-throughput biopharmaceutical characterization, including peptide analysis and intact and native monoclonal antibody measurements. UniDirect offers an efficient alternative to conventional LC-MS workflows for suitable samples, while chromatographic separation remains valuable for complex matrices and applications requiring additional analyte separation.
