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Updated: Jun 26, 2026
09:39
Injectable Supramolecular Polymer-Nanoparticle Hydrogels for Cell and Drug Delivery Applications
Published on: February 7, 2021
Oral insulin delivery using nanoparticles based on microemulsions with different structure-types: optimisation and in
Anja Graf1, Thomas Rades, Sarah M Hook
1School of Pharmacy, University of Otago, P.O. Box 913, Dunedin, New Zealand. anja.graf@otago.ac.nz
Summary
Optimizing insulin entrapment in poly(alkylcyanoacrylate) nanoparticles within microemulsions shows promise for oral delivery. This approach demonstrated effective in vitro release and significant in vivo hypoglycemic effects in diabetic rats.
Area of Science:
- Nanotechnology
- Pharmaceutics
- Biomedical Engineering
Background:
- Oral insulin delivery faces challenges due to degradation in the gastrointestinal tract.
- Poly(alkylcyanoacrylate) nanoparticles offer a potential carrier system for therapeutic proteins.
- Microemulsions can serve as templates for nanoparticle formulation and enhance drug delivery.
Purpose of the Study:
- To optimize the entrapment of insulin within poly(alkylcyanoacrylate) nanoparticles.
- To prepare nanoparticles using microemulsions with varying microstructures.
- To investigate the in vitro release kinetics and in vivo bioactivity of entrapped insulin.
Main Methods:
- Preparation of poly(alkylcyanoacrylate) nanoparticles using microemulsion templates.
- Quantification of insulin entrapment efficiency and release using reverse-phase HPLC.
- Morphological analysis of nanoparticles via scanning electron microscopy.
- In vivo assessment of insulin bioactivity using a streptozotocin-diabetic rat model.
Main Results:
- Spherical nanoparticles (200-400 nm) were consistently produced across different microemulsion templates.
- Entrapment efficiency increased with monomer concentration but decreased with higher aqueous fractions.
- In vitro insulin release was primarily controlled by monomer concentration.
- In vivo studies showed significant, sustained hypoglycemic effects for up to 36 hours without detectable serum insulin levels.
Conclusions:
- Dispersing insulin-loaded nanoparticles in biocompatible microemulsions is a promising strategy for oral insulin delivery.
- Optimization of nanoparticle formulation parameters, including monomer concentration and aqueous fraction, is crucial for efficient insulin entrapment and controlled release.
- The study underscores the importance of integrating in vitro and in vivo evaluations for developing effective nanocarrier systems.
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