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  • Polysaccharide‐based H2S donors: Thiol‐ene functionalization of amylopectin with H2S ‐releasing N ‐thiocarboxyanhydrides
Title: Polysaccharide‐based H2S donors: Thiol‐ene functionalization of amylopectin with H2S ‐releasing N ‐thiocarboxyanhydrides
Abstract Polymeric donors of gasotransmitters, gaseous signaling molecules such as hydrogen sulfide, nitric oxide, and carbon monoxide, hold potential for localized and extended delivery of these reactive gases. Examples of gasotransmitter donors based on polysaccharides are limited despite the availability and generally low toxicity of this broad class of polymers. In this work, we sought to create a polysaccharide H2S donor by covalently attachingN‐thiocarboxyanhydrides (NTAs) to amylopectin, the major component of starch. To accomplish this, we added an allyl group to an NTA, which can spontaneously hydrolyze to release carbonyl sulfide and ultimately H2S via the ubiquitous enzyme carbonic anhydrase, and then coupled it to thiol‐functionalized amylopectin of three different molecular weights (MWs) through thiol‐ene “click” photochemistry. We also varied the degree of substitution (DS) of the NTA along the amylopectin backbone. H2S release studies on the six samples, termed amyl‐NTAs, with variable MWs (three) and DS values (two), revealed that lower MW and higher DS led to faster release. Finally, dynamic light scattering experiments suggested that aggregation increased with MW, which may also have affected H2S release rates. Collectively, these studies present a new synthetic method to produce polysaccharide H2S donors for applications in the biomedical field.  more » « less
Award ID(s):
1933525
PAR ID:
10609465
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Journal of Polymer Science
Volume:
62
Issue:
18
ISSN:
2642-4150
Page Range / eLocation ID:
4155 to 4164
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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