High-Throughput N-Glycan Analysis by IR-MALDESI With a 1.5-kHz Pulsed Mid-IR Laser

Infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) is a laser-based, hybrid ionization source for mass spectrometry, enabling both mass spectrometry imaging (MSI) and high-throughput screening (HTS). In this work, a 2.2-ns, 2.72-μm laser, operating at 1.5 kHz, was integrated into the IR-MALDESI platform to evaluate its performance for robust HTS and glycan profiling. The system produced robust HTS performance, achieving a relative standard deviation (RSD) of 9.1% with no detectable carryover between wells and consistent ion abundances in multiwell screening experiments. Using this configuration, 29 glycans were detected from a solution of cleaved N-glycans derived from bovine fetuin, with multiple charge states observed for several species. These results demonstrate rapid, high-throughput analysis and expanded glycan detection enabled by desorption using a low-power mid-IR laser operating at kHz repetition rates, highlighting its potential for advanced biochemical screening and characterization.