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Updated: Jun 27, 2026
Alternating Magnetic Field-Responsive Hybrid Gelatin Microgels for Controlled Drug Release
Published on: February 13, 2016
Effect of Application of a Homogeneous Magnetic Field During Chemical Crosslinking of Magnetic Collagen-Based
Adriana Gilarska1, Wojciech Horak2, Agnieszka Radziszewska3
1Faculty of Physics and Applied Computer Science, AGH University of Krakow, Mickiewicza 30, 30-059 Krakow, Poland.
Abstract:
The aim of this study was to investigate the effect of a static, homogeneous magnetic field on the physicochemical properties of magnetic hydrogels based on collagen and superparamagnetic iron oxide nanoparticles (SPIONs), chemically crosslinked with genipin. The crosslinking process was initiated in the presence of a magnetic field with three different induction values (100, 250 and 500 mT), generated in specially designed experimental systems. It was demonstrated that the applied field did not noticeably affect the crosslinking efficiency, and stable hydrogels with a high gel fraction in the range of 87-94% were obtained. STEM image analysis revealed that in the highest magnetic field, the nanoparticles tended to form larger clusters, while at lower fields and in the material crosslinked at zero field, smaller clusters and chains of nanoparticles were observed mainly. This observation was reflected in the magnetic susceptibility, which showed a weaker response to the magnetic field of the material obtained by crosslinking in the presence of the 500 mT field compared to the material crosslinked without the field-larger clusters of nanoparticles may hinder the alignment of the magnetic moments of their constituent nanoparticles. Studies of the physicochemical properties of the hydrogels obtained indicate that the presence of larger clusters can cause a local decrease in the crosslinking density, resulting in a slight decrease in the storage modulus and increased initial swelling and degradation rates. The results obtained show that the application of a homogeneous magnetic field with moderate induction values during the crosslinking process can be used as a tool for modification of the microstructure of magnetic collagen-based hydrogels. The possibility of such structural modifications may be useful in designing biomaterials with properties tailored to their target application.
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