Sequencing Biodegradable and Potentially Biobased Polyesteramide of Sebacic Acid and 3-Amino-1-propanol by MALDI TOF-TOF Tandem Mass Spectrometry

Abstract

Biodegradable and potentially biobased polyesteramide oligomers (PEA-Pro), obtained from melt condensation of sebacic acid and 3-amino-1-propanol, were characterized by nuclear magnetic resonance (NMR), matrix assisted laser desorption/ionization-time of flight/time of flight-mass spectrometry/mass spectrometry (MALDI-TOF/TOF-MS/MS), thermogravimetric analysis (TGA), and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). NMR analysis showed the presence of hydroxyl and amino terminal groups as well as carboxylic groups of the sebacate moiety. Hydroxyl and carboxyl termination had the same abundance, while the amine termination was 2.7-times less frequent. Information regarding the fragmentation pathways and ester/amide bond sequences was obtained by MALDI-TOF/TOF-MS/MS analysis performed on sodiated adducts of cyclic species and linear oligomers. Different end groups did not influence the observed fragmentation. Three fragmentation pathways were recognized. The β-hydrogen-transfer rearrangement, which leads to the selective scission of the –O–CH2– bonds, was the main mechanism. Abundant product ions originating from –CH2–CH2– (β–γ) bond cleavage in the sebacate moiety and less abundant ions formed by –O–CO– cleavages were also detected. TGA showed a major weight loss (74%) at 381 °C and a second degradation step (22% weight loss) at 447 °C. Py-GC/MS performed in the temperature range of 350–400 °C displayed partial similarity between the degradation products and the main fragments detected in the MALDI-TOF/TOF-MS/MS experiments. Degradation products derived from amide bonds were related to the formation of CN groups, in agreement with the literature.

Characterization Techniques of Polymer Aging: From Beginning to End

“…Moreover, Rizzarelli et al have carried out the tandem MALDI-TOF/TOF MS/MS analysis for polyesteramide with linear or cyclic structures, and the ester/amide bond sequences and the fragmentation have been detected. 276 Other MS strategies have also been explored for polymer aging 277 such as inductively coupled plasma-mass spectrometry (ICP-MS), 278 MS combined with liquid extraction surface analysis (LESA), 279 and solid-phase extraction. 280 These developed techniques were beneficial for the investment of aging studies for the polymers.…”

Matrix-Assisted Laser Desorption and Electrospray Ionization Tandem Mass Spectrometry of Microbial and Synthetic Biodegradable Polymers

“…MALDI-TOF/TOF-MS/MS has been well used to study biodegradable polymer samples, such as polyesters and polyesteramides [ 19 , 38 ]. It disclosed structural information concerning the sequence of ester and amide bonds in synthetic polyesteramides [ 47 , 49 , 54 ] and the fragmentation mechanisms in biodegradable polyesters [ 48 , 52 ]. Fragmentation studies have been carried out on biodegradable aliphatic polyesters [ 48 , 52 ] and polyesteramides [ 47 , 49 , 54 ] by MALDI CID experiments.…”

“…It disclosed structural information concerning the sequence of ester and amide bonds in synthetic polyesteramides [ 47 , 49 , 54 ] and the fragmentation mechanisms in biodegradable polyesters [ 48 , 52 ]. Fragmentation studies have been carried out on biodegradable aliphatic polyesters [ 48 , 52 ] and polyesteramides [ 47 , 49 , 54 ] by MALDI CID experiments. Selected Na + adducts of poly(butylene adipate) (PBA) oligomers bearing different chain ends were analyzed by MALDI/TOF-TOF CID using air as the collision gas.…”

“…PSD and MALDI-CID analysis with a TOF-TOF instrument was useful in the fragmentation studies of polyesteramide (PEAm). Moreover, MALDI-TOF/TOF-MS/MS was successfully applied in the determination of the sequence of the ester, and the amide bonds as well as the structure elucidation of side products originated during the polymerization reaction in PEAm samples [ 47 , 49 , 54 ]. In particular, PSD and MALDI CID have been used to characterize PEAm synthesized through a melt condensation of sebacic acid and 4-amino-1-butanol.…”

“…In the last decades, studies on fragmentation mechanisms [ 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 ], structure and architecture [ 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 ], biopharmaceutical and drug delivery systems (DDS) [ 89 , 90 , 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 , 100 , 101 , …”