25 May Improving Sensitivity of GLP-1 Analogues Quantitation Using Multiple Spray ESI Technology on a Microflow LC-MS/MS

I would like to thank Kathleen Luo et.al of Shimadzu Scientific Instruments for sharing her poster from ASMS 2025 entitled Improving Sensitivity of GLP-1 Analogues Quantitation Using Multiple Spray ESI Technology on a Microflow LC-MS/MS. It was nice to see the CERI L-Columns used in the analysis. The following is directly highlighted from the poster.

• Glucagon-like peptide-1 (GLP-1) receptor agonists — a class of biotherapeutic drugs used to treat type 2 diabetes and obesity — have seen rapid growth in development over the past decade. However, these larger molecules present unique analytical challenges compared to traditional small-molecule drugs, including poor ionization efficiency, limited MS/MS fragmentation, and sample carryover.
• To address these issues, a multiple-spray electrospray ionization (ESI) approach was evaluated. This design uses a multi-nozzle emitter, which enhances ionization efficiency and boosts sensitivity compared to conventional single-nozzle emitters (Figure 1).
  · Various analytical and trap columns were also tested for their compatibility with this workflow. Reverse-phase columns with C4 to C18 functionalities were compared based on analyte retention, peak shape, and carryover performance.
• The optimized column combination demonstrated less than 0.1% carryover at a concentration of 200 ng/mL.
• Trap Column CERI L-column2 C8 Cartridge 0.3 mm x 5 mm, 5 μm.
• Analytical Column: CERI L-column2 C8 Column 0.2 mm x 50 mm, 3 μm

This study highlights the potential of microflow-LC systems coupled with microflow ionization sources to deliver enhanced sensitivity and low carryover for GLP-1 peptide analysis — all achievable using existing mass spectrometry platforms.

Please see the poster below.