Hydrogel Strain Sensors for Integrating Into Dynamic Organ-on-a-Chip

Area of Science:

• Biomedical Engineering
• Materials Science
• Microfluidics

Background:

• Current hydrogel strain sensors lack sensitivity in aqueous cell culture environments, limiting their integration into organ-on-a-chip (OOC) systems.
• Developing sensitive and stable strain sensors is crucial for mimicking physiological conditions in dynamic OOC models.

Purpose of the Study:

• To develop a novel, highly sensitive hydrogel strain sensor for integration into dynamic organ-on-a-chip (OOC) systems.
• To demonstrate the sensor's capability in monitoring physiological and pathological conditions within a lung-on-a-chip (LOC) model.

Main Methods:

• Fabrication of a strain sensor by coating a MXene layer on a pre-stretched, anti-swelling hydrogel substrate (di-acrylated Pluronic F127 and chitosan).
• Cultivation of alveolar epithelial cells on the hydrogel sensor to form alveolar barriers.
• Integration of the sensor-cell construct into dynamic lung-on-a-chip (LOC) systems.

Main Results:

• The fabricated strain sensors exhibited high sensitivity (gauge factor of 290.96), a wide sensing range (0-100%), and excellent repeatability.
• The sensor successfully monitored normal physiological breathing in the LOC system.
• The system effectively detected pathological inflammation induced by lipopolysaccharide (LPS) and its alleviation through drug intervention.

Conclusions:

• The novel hydrogel strain sensor overcomes previous limitations, enabling sensitive monitoring in dynamic OOC and LOC systems.
• This technology provides a powerful tool for studying lung physiology, disease, and drug responses in vitro.
• The sensor's high sensitivity and stability open avenues for advanced OOC applications.