Mass spectrometry for the elucidation of the subtle molecular structure of biodegradable polymers and their degradation products

Abstract

Contemporary reports by Polish authors on the application of mass spectrometric methods for the elucidation of the subtle molecular structure of biodegradable polymers and their degradation products will be presented. Special emphasis will be given to natural aliphatic (co)polyesters (PHA) and their synthetic analogues, formed through anionic ring-opening polymerization (ROP) of b-substituted b-lactones. Moreover, the application of MS techniques for the evaluation of the structure of biodegradable polymers obtained in ionic and coordination polymerization of cyclic ethers and esters as well as products of step-growth polymerization, in which bifunctional or multifunctional monomers react to form oligomers and eventually long chain polymers, will be discussed. Furthermore, the application of modern MS techniques for the assessment of polymer degradation products, frequently bearing characteristic end groups that can be revealed and differentiated by MS, will be discussed within the context of specific degradation pathways. Finally, recent Polish accomplishments in the area of mass spectrometry will be outlined. # 2015 Wiley Periodicals, Inc. Mass Spec Rev 35: 188-198, 2016.

Oxidized Polyethylene Wax as a Potential Carbon Source for PHA Production

“…The ESI-MS/MS spectrum of sodium adduct at m / z 911 also showed the fragment ion at m / z 811, grouped in a cluster containing three fragment ions, which may correspond to oligomers having the same degree of polymerization but having a different a content of HB and HV units. The fragmentation results allowed us to confirm that in the presence of O-PEW carbon source the PHA formed was composed of 3-hydroxybutyrate, 3-hydroxyvareate as well as 3-hydroxyhexanoate co-monomer units which are randomly distributed along the oligomer chain [34,38,40]. Moreover, with respect to the hitherto reported studies, this research demonstrated the possibility of PHA structure evaluation even when the content of HV and HH is lower than 5%, i.e.…”

“…Development of soft ionization techniques in mass spectrometry made the attempt to solve the difficult question regarding the molecular structure of copolymers more likely. Thus, structural studies of biodegradable copolymers with the use of multi-stage electrospray mass spectrometry (ESI-MS n ) were performed [38]. This mass spectrometry technique was applied to determine the co-monomer unit composition and composition distribution in bacterial PHA copolymers based on the analysis of their oligomers obtained by partial depolymerization (Figure 4).…”

“…Thus, the fragmentation spectrum acquired for the precursor ion at m / z 897 confirms the presence of 3-hydroxybutyrate and the 3-hydroxyvalerate co-monomer units in polyester chains. Moreover, such a fragmentation pathway indicates that the 3HV unit is randomly distributed along the oligomer chain [38,40,41]. …”

Controlled biodegradation of polymers using nanoparticles and its application

“…The assessment of polymer degradation products having characteristic end groups was revealed and differentiated by the application of modern MS techniques [110]. The assessment of polymer degradation products having characteristic end groups was revealed and differentiated by the application of modern MS techniques [110].…”

Polymers Tailored for Controlled (Bio)degradation Through End-Group and In-Chain Functionalization

“…The anionic ROP of β-substituted βlactones seems to be a perfect tool for the preparation of analogues of natural aliphatic biopolyesters, PHAs with the desired molecular structure, including the structure of the end groups [75]. Using this approach, with the aid of metalfree anionic initiators, block and random synthetic PHA copolymers can be prepared by anionic ROP of βbutyrolactone with comonomeric β-substituted β-lactones and characterized at the molecular level [76].…”