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Monitoring polydispersity by NMR diffusometry with tailored norm regularisation and moving-frame processing
Mateusz Urbańczyk1, Diana Bernin2, Alan Czuroń3
1Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warszawa, Poland and Centre of New Technologies, University of Warsaw, ul. Banacha 2C, 02-097 Warsaw, Poland. k.kazimierczuk@cent.uw.edu.pl.
The Analyst
|January 30, 2016
Summary
A new nuclear magnetic resonance (NMR) method generalizes ITAMeD using tailored lp-norm to analyze polydisperse samples. This approach accurately monitors diffusion coefficients and polydispersity changes in real-time during enzymatic degradation.
Area of Science:
- Analytical Chemistry
- Physical Chemistry
- Polymer Science
Background:
- Nuclear magnetic resonance (NMR) is a key analytical technique in chemistry.
- NMR can monitor reactions over extended periods and analyze complex mixtures using diffusion coefficients.
- Extracting diffusion coefficient distributions via inverse Laplace transform (ILT) is challenging due to noise and instability.
Purpose of the Study:
- To generalize the ITAMeD method for analyzing polydisperse samples using NMR.
- To develop a robust method for extracting diffusion coefficient distributions from noisy NMR signals.
- To monitor real-time changes in diffusion coefficients and polydispersity during enzymatic degradation.
Main Methods:
- Proposed a generalized ITAMeD method employing a tailored lp-norm (1 ≤ p ≤ 2).
- Applied the method to simulations and experimental datasets of polyethylene oxides with varying polydispersity.
- Utilized the method to track diffusion and polydispersity of heparin during enzymatic degradation.
Main Results:
- The generalized ITAMeD method successfully processed signals from polydisperse samples.
- Demonstrated accurate monitoring of diffusion coefficient and polydispersity changes in real-time.
- Validated the method's performance on both simulated and experimental data.
Conclusions:
- The generalized ITAMeD method offers a powerful tool for analyzing polydisperse systems using NMR.
- This technique enables real-time monitoring of dynamic changes in diffusion and molecular characteristics.
- The study advances NMR-based analysis for complex chemical and biological systems.
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