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Nitric oxide-releasing photocrosslinked chitosan cryogels
Herllan Vieira de Almeida1, Laura Caetano Escobar da Silva1, Marcelo Ganzarolli de Oliveira1
1Institute of Chemistry, University of Campinas, UNICAMP, Campinas, SP, Brazil.
Nitric Oxide : Biology and Chemistry
|April 5, 2024
Summary
Researchers developed porous chitosan cryogels that release nitric oxide (NO) upon hydration. These novel biomaterials offer potential for localized NO delivery in medical applications.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Nanotechnology
Background:
- Chitosan cryogels possess porous structures ideal for biomaterial applications requiring hydration-triggered responses.
- Nitric oxide (NO) releasing biomaterials are crucial for various biomedical applications, with NO release often dependent on material hydration.
- Developing effective NO-releasing platforms necessitates materials with controlled porosity and rapid water absorption.
Purpose of the Study:
- To engineer chitosan cryogels (CS) capable of releasing nitric oxide (NO) triggered by rapid hydration.
- To functionalize CS with S-nitrosothiols (SNO) to create a NO-releasing system.
- To investigate the NO release kinetics from the functionalized chitosan cryogels.
Main Methods:
- Chitosan was methacrylated and photocrosslinked, followed by freeze-drying to create a porous cryogel structure.
- The porous chitosan cryogels were functionalized with S-nitrosothioglycolic acid (TGA(SNO)) and S-nitrosomercaptosuccinic acid (MSA(SNO)) using carbodiimide-mediated reactions.
- Chemiluminescence measurements were employed to quantify the nitric oxide release rates upon water absorption.
Main Results:
- The developed chitosan cryogels exhibited a porous morphology with interconnected cells and wall thicknesses ranging from 340-881 nm.
- Functionalized cryogels (CS-TGA(SNO) and CS-MSA(SNO)) demonstrated spontaneous NO release upon hydration.
- Specific NO release rates were measured: 3.34 × 10⁻² nmol mg⁻¹ min⁻¹ for CS-TGA(SNO) and 1.27 × 10⁻¹ nmol mg⁻¹ min⁻¹ for CS-MSA(SNO).
Conclusions:
- The study successfully developed porous chitosan cryogels functionalized with S-nitrosothiols for NO delivery.
- The rapid hydration-triggered NO release mechanism opens new avenues for localized NO delivery in biomedical applications.
- These functionalized chitosan cryogels represent a promising platform for advanced therapeutic strategies.
Keywords:
ChitosanCryogelPhotocrosslinkingS-nitrosomercaptosuccinic acidS-nitrosothioglycolic acidS-nitrosothiolsMore Related Videos
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