Advances in Injectable Hydrogels Based on Diverse Gelation Methods for Biomedical Imaging

Area of Science:

• Biomaterials Science
• Drug Delivery
• Medical Imaging

Background:

• Injectable hydrogels offer precise delivery and localized retention of therapeutic loads.
• Hydrogel gelation is triggered by various stimuli including temperature, ions, enzymes, light, mechanics, and pH.
• Tracking the in vivo behavior (injection, degradation, drug release) of injectable hydrogels is challenging.

Purpose of the Study:

• To review methods for creating imageable injectable hydrogels.
• To discuss the application of contrast agent-loaded hydrogels in various imaging modalities.
• To explore the potential and challenges of imageable hydrogels based on different gelation mechanisms.

Main Methods:

• Review of literature on imageable injectable hydrogels.
• Analysis of contrast agent incorporation strategies.
• Discussion of various gelation triggers and their impact on imaging.

Main Results:

• Contrast agents enable visualization of hydrogels using fluorescence, photoacoustic, MRI, and radionuclide imaging.
• Imageable hydrogels allow for real-time monitoring of injection site, degradation, and drug release.
• Different gelation methods influence the feasibility and effectiveness of imaging.

Conclusions:

• Imageable injectable hydrogels offer significant advantages for monitoring therapeutic delivery.
• Further research is needed to optimize imageable hydrogel design and address current challenges.
• These advanced hydrogels hold great promise for precision medicine and theranostics.