Structural and end-group analysis of synthetic acrylate co-polymers by matrix-assisted laser desorption time-of-flight mass spectrometry: Distribution of pendant carboxyl groups

A generally accepted strategy in the development of polymers for interaction with biological systems is control of chemically active functional groups and their concentration within polymer chains. From that perspective, there is a strong need for careful study of polymer structure and distribution of pendant functional groups within macromolecules. One of the materials of particular interest is polymethyl methacrylate-co-methacrylic acid (PMMA-co-MAA). We have performed a detailed matrix-assisted laser desorption time-off-flight mass spectrometry (MALDI-ToF-MS) characterization of PMMA-co-MAA (synthesized with different monomer ratios) in order to establish the molecular mass distribution, polymer end groups and exact molecular structures present in the polymer systems. Experimental results have confirmed the successful formation of the materials, based on pre-determined theoretical compositions, with close control over macromolecular structure. Furthermore, a detailed structural analysis of each composition has provided valuable information about the variation of concentration of carboxyl functional groups, generated from MAA co-polymer segments.