Alkyl Chloride-Functionalized Polymers Mediate Oxidation of Thioethers Initiated by Ionizing Radiation
Juncheng Liu1,2, Irene Piergentili1, Bing Xu1,2
1Department of Chemical Engineering, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, Netherlands.
ACS Applied Polymer Materials
|April 3, 2025
Summary
Polymeric alkyl chlorides generate peroxyl radicals for drug delivery applications. This research explores their potential as an alternative to small-molecule alkyl chlorides in anticancer therapy.
Area of Science:
- Radiochemistry
- Polymer Chemistry
- Drug Delivery Systems
Background:
- Alkyl chlorides generate peroxyl radicals via reactions with aqueous electrons and oxygen.
- Peroxyl radicals oxidize thioethers to sulfoxides, a key reaction for drug delivery.
- Small-molecule alkyl chlorides pose toxicity risks, limiting their therapeutic use.
Purpose of the Study:
- To investigate polymeric alkyl chlorides as a safer alternative to small-molecule counterparts.
- To assess the accessibility of alkyl chloride functionalities on a hydrophilic copolymer chain.
- To evaluate the potential of polymeric alkyl chlorides in drug delivery and anticancer therapy.
Main Methods:
- Irradiation of aqueous solutions containing alkyl chlorides and hydrophilic random copolymers.
- Characterization of peroxyl radical generation and subsequent oxidation reactions.
- Assessment of alkyl chloride accessibility on the polymer backbone.
Main Results:
- Polymeric alkyl chlorides, when bound to a hydrophilic random copolymer, exhibit similar reactivity to small-molecule alkyl chlorides.
- The accessibility of alkyl chloride functionalities on the polymer chain is crucial for electron interactions.
- This approach offers a potential strategy to mitigate the toxicity associated with small-molecule alkyl chlorides.
Conclusions:
- Polymeric alkyl chlorides can serve as a viable alternative to small-molecule versions for generating peroxyl radicals.
- The development of accessible polymeric alkyl chlorides could advance targeted or triggered drug delivery systems.
- Further research into the precise control of alkyl chloride accessibility on polymers is warranted for therapeutic applications.
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