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Updated: Jul 18, 2026
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Injectable Supramolecular Polymer-Nanoparticle Hydrogels for Cell and Drug Delivery Applications
Published on: February 7, 2021
Probing insulin's secondary structure after entrapment into alginate/chitosan nanoparticles
B Sarmento1, D C Ferreira, L Jorgensen
1Department of Pharmaceutical Technology, Faculty of Pharmacy of the University of Porto, Porto, Portugal. bruno.sarmento@ff.up.pt
Summary
Chitosan/alginate nanoparticles effectively encapsulate insulin, preserving its structure. This indicates potential for successful oral insulin delivery, maintaining bioactivity.
Area of Science:
- Biomaterials Science
- Drug Delivery Systems
- Nanotechnology
Background:
- Insulin therapy often relies on injections, limiting patient compliance.
- Developing oral insulin delivery systems is crucial for improving diabetes management.
- Chitosan and alginate are biocompatible polymers with potential for nanoparticle formulation.
Purpose of the Study:
- To evaluate the structural integrity of insulin encapsulated within chitosan/alginate nanoparticles.
- To investigate the influence of nanoparticle formulation parameters on insulin structure.
- To assess the potential of this nanoparticulate system for oral insulin delivery.
Main Methods:
- Ionotropic polyelectrolyte pre-gelation was used to produce chitosan/alginate nanoparticles.
- Alginate:chitosan ratio and pH were optimized for nanoparticle size and insulin association efficiency.
- Fourier transform infrared (FTIR) spectroscopy and circular dichroism (CD) were employed to analyze insulin's secondary structure.
Main Results:
- Optimized nanoparticle production yielded a mean size of 850 nm with 81% insulin association efficiency.
- FTIR and CD analyses confirmed no significant changes in insulin's alpha-helix and beta-sheet content post-encapsulation and release.
- Insulin structure was preserved during nanoparticle production and simulated gastrointestinal conditions.
Conclusions:
- Chitosan/alginate nanoparticles maintain insulin's structural integrity.
- The developed nanoparticulate system shows promise as a carrier for oral insulin delivery.
- Preservation of insulin structure suggests potential for maintained bioactivity and therapeutic efficacy.
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