Engineering Soft Spring Gauges for In Situ Biomaterial and Tissue Weighing

Area of Science:

• Biomaterials Science
• Biomedical Engineering

Background:

• Hydrogels are widely used in tissue engineering, regenerative medicine, and drug delivery due to their biocompatibility and biodegradability.
• Accurate and noninvasive characterization of hydrogel degradation is crucial but challenging.

Purpose of the Study:

• To develop a novel method for in situ hydrogel weighing.
• To enable accurate and noninvasive monitoring of hydrogel degradation processes.

Main Methods:

• Fabrication of polydimethylsiloxane (PDMS) soft spring gauges (SSGs) using a hydrogel-based sacrificial template.
• Utilizing the linear correlation between SSG length change and applied weight for mass determination.
• In situ weighing of hydrogels in buffer solutions to track degradation.

Main Results:

• Developed SSGs capable of weighing hydrogels with a minimum wet weight of approximately 30 mg.
• Confirmed the linear relationship between SSG length change and hanging weight through theoretical, numerical, and experimental analyses.
• Successfully demonstrated the feasibility and accuracy of SSGs for tracking hydrogel solid mass change during degradation.
• Showcased the potential application of SSGs for in situ characterization of engineered tissue growth.

Conclusions:

• The developed SSG method provides an advanced approach for in situ hydrogel weighing.
• This technique offers high feasibility and accuracy for monitoring hydrogel degradation and engineered tissue development.
• The SSG method holds significant promise for advancing hydrogel and biomaterial research in biomedical applications.