A Nanoparticle Ink Allowing the High Precision Visualization of Tissue Engineered Scaffolds by MRI
Samila Leon-Chaviano1,2, Mariia Kiseleva1,2, Philippe Legros1,2
1Centre de Recherche du Centre Hospitalier Universitaire de Québec - Université Laval (CR CHUQ), Axe Médecine Régénératrice, Quebec City, Québec, G1L 3L5, Canada.
Small (Weinheim an Der Bergstrasse, Germany)
|March 25, 2023
Summary
This study introduces a magnetic ink using ultra-small iron oxide nanoparticles to improve MRI contrast for hydrogel cell scaffolds. The new magnetic hydrogel offers precise visualization and monitoring of tissue grafts without image artifacts.
Area of Science:
- Biomaterials Science
- Medical Imaging
- Nanotechnology
Background:
- Hydrogels are crucial as cell scaffolds in biomedical applications but suffer from poor contrast in Magnetic Resonance Imaging (MRI).
- Existing contrast agents for hydrogels can cause image artifacts, hindering precise visualization of implants.
- MRI is ideal for imaging water-rich tissues, making contrast enhancement critical for hydrogel scaffolds.
Purpose of the Study:
- To develop and evaluate a novel magnetic ink for enhancing MRI contrast in alginate hydrogel cell scaffolds.
- To assess the biocompatibility, relaxometric properties, and in vivo MR-visibility of the magnetic hydrogel.
- To demonstrate precise delineation and monitoring of hydrogel implants using MRI.
Main Methods:
- Integration of ultra-small iron oxide nanoparticles (USPIONs) into biocompatible alginate hydrogels.
- Measurement of relaxometric properties, biocompatibility, and MR-visibility (T1-weighted) in vitro and in vivo.
- A 2-week in vivo MRI follow-up study in a mouse model.
Main Results:
- The magnetic hydrogel demonstrated "positive" contrast in MRI without artifacts.
- Precise delineation of tissue grafts was achieved over a 2-week period.
- A 3D-contouring procedure was successfully applied for geometrical assessment.
Conclusions:
- USPION-based magnetic ink provides high-visibility for precisely engineered hydrogel structures.
- This approach enables artifact-free, precise delineation and long-term monitoring of hydrogel implants via MRI.
- The developed magnetic hydrogel shows significant potential for advanced cell scaffolding and biomedical imaging applications.
