Polymers that respond to oxidants
Nicola Tirelli
Researcher (tenured); IIT Associate Director for Education, Polymers and Biomaterials

Jan. 26, 2023, 1 p.m.
This seminar is held online.
Online: https://tinyurl.com/nanoSeminar-GA

Google Scholar


This talk is about organic macromolecules containing sulphur(II) species, mostly in the form of thioethers (sulfides).
The main characteristic of such materials is the capacity to react with oxidants (including biologically relevant inflammatory mediators), which turn sulphur to higher oxidation states. This can determine large changes in polarity, and trigger reorganizations in self-assembly, as well as the delivery of encapsulated molecules.
In our group, we have long experience with such a class of materials, ranging from the application of synthetic techniques for the fine control over primary structure [1] or macromolecular architecture [2], to their use directly as therapeutic agents (due to the anti-inflammatory effects of ROS removal) [3] or their oxidatively stimulated release of pharmaceutically active agents [4].
In the talk we will review the current state of knowledge in terms of synthetic techniques and biomedical applications for both polysulfides and polythioacetals, focusing on the differential sensitivity of these sulphur groups to oxidants: thioethers, for example, are substantially unresponsive to some oxidants such as superoxide, which on the contrary react readily with polysulfides. We will also discuss the combination of oxidation responsiveness with e.g. thermal sensitivity.
We will then finally focus on the concept of sacrificial oxidation, where the action of scavenging biologically relevant oxidants (Reactive Oxygen Species, ROS), is used to increase the stability of cargos (proteins) against oxidative damage in a biological environment [5].

1. R. d’Arcy et al., Macromolecules, 2015,. DOI:10.1021/acs.macromol.5b02007
2. R. Pérez-Camargo, et al., Macromolecules, 2019, DOI: 10.1021/acs.macromol.8b02659
3. O. Rajkovic et al., Adv. Ther. 2019 DOI:10.1002/adtp.201900038
4. F. El Mohtadi et al., Biomacromolecules, 2020 DOI: 10.1021/acs.biomac.9b01348A
5. R. d’Arcy, et al. Journal of the American Chemical Society, 2022 DOI: 10.1021/jacs.2c09232V


Brief CV

Nicola was born in Rome. He spent his childhood in the quiet town of Pisa, and his teenager and University years in its even quieter outskirts.

In the last year of his PhD, he moved to the ETH Zurich, as a guest of the group of Macromolecular Chemistry (Dept. of Materials) then led by Ueli Suter. Having grown very fond of the group, the institution, the town, and the Swiss way of life that, he then stayed as a postdoc until the end of 1997; during this period, he unsuccessfully tried to learn the intricacies of polymer physics, but became firmly convinced that it is complicated. Quoting from the Master thesis of a later mentor of his, Nicola's use of polymer physics is similar to that of a drunkard for a lamp post: more for support than for illumination.

Between 2006 and 2012 he had fun as the editor in chief of Reactive & Functional Polymers (a journal of Elsevier), which he left when it became less fun and more a job.

At the UoM, Nicola helped establishing the MRes course in Tissue Engineering and Regenerative Medicine (BBRSC grants: BB/H015868/1 and BB/H021205/1), the NOWNANO Doctoral Training Centre ("A North West Nanoscience Doctoral Training Centre"; 2009-2018; EPSRC grant: EP/G03737X/1) and the Centre of Doctoral Training in Regenerative Medicine (2014-running; co-director 2014-15, director 2016-17; EPSRC/MRC grant EP/L014904/1).

Nicola has published >170 paper. H-index 48 (Google Scholar) / 44 (Scopus).



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Polymers that respond to oxidants
Nicola Tirelli
Researcher (tenured); IIT Associate Director for Education, Polymers and Biomaterials

Jan. 26, 2023, 1 p.m.
This seminar is held online.
Online: https://tinyurl.com/nanoSeminar-GA

Google Scholar


This talk is about organic macromolecules containing sulphur(II) species, mostly in the form of thioethers (sulfides).
The main characteristic of such materials is the capacity to react with oxidants (including biologically relevant inflammatory mediators), which turn sulphur to higher oxidation states. This can determine large changes in polarity, and trigger reorganizations in self-assembly, as well as the delivery of encapsulated molecules.
In our group, we have long experience with such a class of materials, ranging from the application of synthetic techniques for the fine control over primary structure [1] or macromolecular architecture [2], to their use directly as therapeutic agents (due to the anti-inflammatory effects of ROS removal) [3] or their oxidatively stimulated release of pharmaceutically active agents [4].
In the talk we will review the current state of knowledge in terms of synthetic techniques and biomedical applications for both polysulfides and polythioacetals, focusing on the differential sensitivity of these sulphur groups to oxidants: thioethers, for example, are substantially unresponsive to some oxidants such as superoxide, which on the contrary react readily with polysulfides. We will also discuss the combination of oxidation responsiveness with e.g. thermal sensitivity.
We will then finally focus on the concept of sacrificial oxidation, where the action of scavenging biologically relevant oxidants (Reactive Oxygen Species, ROS), is used to increase the stability of cargos (proteins) against oxidative damage in a biological environment [5].

1. R. d’Arcy et al., Macromolecules, 2015,. DOI:10.1021/acs.macromol.5b02007
2. R. Pérez-Camargo, et al., Macromolecules, 2019, DOI: 10.1021/acs.macromol.8b02659
3. O. Rajkovic et al., Adv. Ther. 2019 DOI:10.1002/adtp.201900038
4. F. El Mohtadi et al., Biomacromolecules, 2020 DOI: 10.1021/acs.biomac.9b01348A
5. R. d’Arcy, et al. Journal of the American Chemical Society, 2022 DOI: 10.1021/jacs.2c09232V


Brief CV

Nicola was born in Rome. He spent his childhood in the quiet town of Pisa, and his teenager and University years in its even quieter outskirts.

In the last year of his PhD, he moved to the ETH Zurich, as a guest of the group of Macromolecular Chemistry (Dept. of Materials) then led by Ueli Suter. Having grown very fond of the group, the institution, the town, and the Swiss way of life that, he then stayed as a postdoc until the end of 1997; during this period, he unsuccessfully tried to learn the intricacies of polymer physics, but became firmly convinced that it is complicated. Quoting from the Master thesis of a later mentor of his, Nicola's use of polymer physics is similar to that of a drunkard for a lamp post: more for support than for illumination.

Between 2006 and 2012 he had fun as the editor in chief of Reactive & Functional Polymers (a journal of Elsevier), which he left when it became less fun and more a job.

At the UoM, Nicola helped establishing the MRes course in Tissue Engineering and Regenerative Medicine (BBRSC grants: BB/H015868/1 and BB/H021205/1), the NOWNANO Doctoral Training Centre ("A North West Nanoscience Doctoral Training Centre"; 2009-2018; EPSRC grant: EP/G03737X/1) and the Centre of Doctoral Training in Regenerative Medicine (2014-running; co-director 2014-15, director 2016-17; EPSRC/MRC grant EP/L014904/1).

Nicola has published >170 paper. H-index 48 (Google Scholar) / 44 (Scopus).



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