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Published on: November 4, 2021
Non-invasive tracking of hydrogel degradation using upconversion nanoparticles
Yuqing Dong1, Guorui Jin2, Changchun Ji2
1State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, PR China; The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, PR China; Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an 710049, PR China.
Upconversion nanoparticles (UCNPs) offer a non-invasive method to track hydrogel degradation in vivo. Their fluorescence intensity accurately reflects hydrogel breakdown, enabling long-term monitoring without harming organs.
Area of Science:
- Biomaterials Science
- Nanotechnology
- Medical Imaging
Background:
- Tracking hydrogel distribution and degradation in vivo is crucial for tissue engineering and drug delivery.
- Fluorescence imaging offers high sensitivity and ease of operation for such tracking applications.
- Existing fluorescent probes like quantum dots can suffer from photobleaching and toxicity.
Purpose of the Study:
- To develop a facile and non-invasive method for tracking hydrogel distribution and degradation in vivo using upconversion nanoparticles (UCNPs).
- To evaluate the accuracy and efficacy of UCNPs as fluorescent probes for monitoring hydrogel fate after transplantation.
- To demonstrate the potential of UCNPs for longitudinal, deep-tissue imaging of biomaterials.
Main Methods:
- Encapsulating UCNPs within hydrogels for in vivo tracking.
- Monitoring changes in UCNP fluorescence intensity to assess hydrogel degradation.
- Comparing UCNP fluorescence data with fluorescein isothiocyanate (FITC) conjugation and hydrogel weight changes.
- Assessing in vivo fluorescence signals and organ health in model rats after hydrogel implantation.
Main Results:
- UCNP fluorescence intensity changes correlated well with hydrogel degradation, as confirmed by FITC conjugation and weight loss.
- UCNPs provided clear in vivo fluorescence signals even after 7 days, unlike FITC, due to deep tissue penetration.
- No discernible damage to major organs was observed in rats, indicating the biocompatibility of the UCNP-hydrogel system.
- UCNPs enabled longitudinal, non-invasive monitoring of hydrogel degradation in deep tissues.
Conclusions:
- UCNPs provide an accurate and reliable method for non-invasive, in vivo tracking of hydrogel degradation.
- The deep tissue penetration and stability of UCNPs make them superior to traditional fluorescent probes for long-term monitoring.
- This UCNP-based approach holds significant potential for clinical translation in monitoring biomaterials and tissue regeneration.
