Related Experiment Video
Updated: Sep 13, 2025

Characterization of Synthetic Polymers via Matrix Assisted Laser Desorption Ionization Time of Flight MALDI-TOF Mass Spectrometry
Published on: June 10, 2018
Comonomer distribution analysis of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)s using high-resolution MALDI-TOF
Naoki Kanayama1, Sayaka Nakamura1, Shin Sano2
1Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan. n.kanayama@aist.go.jp.
Abstract:
In practical applications of poly(3-hydroxybutyrate) (PHB) copolyesters, the distribution of comonomer units within the polymer chains (i.e., comonomer distribution) is an important factor influencing various material properties, alongside the comonomer structure and content. However, analytical methodologies for the characterisation and representation of comonomer distribution in PHB copolyesters remain limited. In the present study, we examined the comonomer distribution in poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) using matrix-assisted laser desorption/ionisation spiral time-of-flight mass spectrometry (MALDI-spiral-TOF-MS). High-molecular-weight PHBH samples were partially methanolysed and subsequently fractionated by size-exclusion chromatography to yield oligomers of suitable molecular sizes for analysis. The high-resolution capabilities of MALDI-spiral-TOF-MS enabled the separation of ion peaks with similar m/z values in the PHBH oligomers and the determination of their accurate masses. The resulting mass spectral data were subsequently subjected to Kendrick mass defect (KMD) analysis to classify ion peaks according to their end-group structures, thereby facilitating the identification of distinct molecular species. Accurate mass measurements enabled the unambiguous determination of the corresponding molecular formulae, end groups, and monomer compositions of the PHBH oligomers. By organising the ion peak data corresponding to PHBH chains of a specific length (e.g., 21-mer), the distribution of 3-hydroxyhexanoate (3HH) units within the molecular chain was represented as a number distribution plot for that chain length. This analytical approach was also succesfully applied to PHBH film residues subjected to biodegradation in seawater.
More Related Videos
05:05Quantification of Polybutylene Adipate Terephthalate-based Micro- and Nano-plastics from Soil Using Proton Nuclear Magnetic Resonance Spectroscopy
Published on: June 6, 2025
09:34Improved Polymerase Chain Reaction-restriction Fragment Length Polymorphism Genotyping of Toxic Pufferfish by Liquid Chromatography/Mass Spectrometry
Published on: September 20, 2016
Related Concept Videos
High-Resolution Mass Spectrometry (HRMS)
Polymers: Molecular Weight Distribution
Mass Spectrometry: Complex Analysis
GC–MS is a powerful hyphenated method commonly used in forensics and environmental...
¹H NMR: Complex Splitting
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied...
Mass Spectrometry: Branched Alkane Fragmentation
Mass Spectrometry: Long-Chain Alkane Fragmentation