Weak Bond-Based Injectable and Stimuli Responsive Hydrogels for Biomedical Applications.

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Biomedical Engineering

Background:

• Physical hydrogels are crosslinked by reversible, weak bonds, offering unique properties like shear thinning and stimuli-responsiveness.
• Unlike traditional hydrogels, they do not require chemical triggers for in situ gelation, enabling efficient drug loading and minimal leakage.
• Their dynamic nature makes them promising for biomedical applications, particularly in drug delivery and tissue engineering.

Purpose of the Study:

• To review recent advances in physical hydrogels crosslinked by various weak interactions.
• To highlight the unique properties and advantages of physical hydrogels for biomedical applications.
• To explore the potential of these dynamic materials for future breakthroughs in drug delivery and tissue engineering.

Main Methods:

• Review of literature on physical hydrogels and their crosslinking mechanisms.
• Analysis of different types of weak interactions used in physical hydrogel formation (hydrogen bonds, ionic interactions, host-guest chemistry, hydrophobic interactions, coordination bonds, π-π stacking).
• Discussion of the properties and applications of these hydrogels in biomedical engineering.

Main Results:

• Physical hydrogels exhibit reversible bonding, shear thinning, and stimuli-responsiveness.
• They allow for pre-formed hydrogel drug loading with minimal cargo leakage during injection.
• Recent advances focus on diverse weak interactions for tailored hydrogel properties.

Conclusions:

• Physical hydrogels are versatile platforms for drug delivery and tissue engineering due to their dynamic and reversible crosslinking.
• Understanding the principles of weak bond crosslinking is crucial for developing next-generation biomaterials.
• These materials hold significant potential for advancing biomedical research and clinical applications.