Synthesis and Molecular Characterization of Pyrene-Containing Copolymers as Potential MALDI-TOF MS Matrices

Due to its exceptional sensitivity, accuracy, and speed, matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry has emerged as a vital analytical tool, especially for the determination of low-molecular-weight compounds (e.g., lipids, metabolites). Continuous advancements in MALDI-TOF technology have expanded its applications. The employment of polymeric materials as matrices has proven to be effective in overcoming significant challenges (self-ionization and adduct formation), particularly those related to interfering background signals in the low-molecular-weight region, making the development of effective matrices a critical area of research. We investigated the synthesis of well-defined polymers that meet the requirements of a suitable matrix for MALDI-TOF MS. In this study, pyrene was chosen as a chromophore to enhance the optical properties of the polymers, taking advantage of its aromatic structure and prominent absorption capabilities. We present the detailed synthesis of novel linear polymers through reversible addition-fragmentation chain transfer polymerization, which afforded macromolecules in a controlled manner and with narrow dispersity (Đ). Reactivity ratios were calculated to provide insight into the copolymerization behavior, allowing precise control over the polymer composition. Finally, these pyrene-incorporating polymers were tested and evaluated for their applicability as MALDI-TOF matrices, particularly in the analysis of low-molecular-weight compounds. Their performance was assessed based on analyte signal intensities and in comparison with other commercially available polymeric matrices (P3DDT), highlighting their potential as robust tools for mass spectrometric analysis.