Boosting Piezoelectricity and Mechanical Properties of Silk Fibroin Films via Polyethylene Glycol Phase Manipulation

Clinical Snapshot

Key Findings

• P Value: Not reported in abstract

• Effect Size: Piezoelectric sensitivity increased 5-fold (0.04 to 0.2 mV/N·μm), tensile strength increased 62% (6.1 to 9.92 MPa)

• Primary Outcome: Enhanced piezoelectric force sensitivity and mechanical properties

• Nnt Or Sensitivity: Piezoelectric force sensitivity: 0.2 mV/N·μm (PEG 2000 Da) vs 0.04 mV/N·μm (pure RSF)

• Confidence Interval: Not reported in abstract

Clinical Application

High feasibility given biodegradable nature and demonstrated human motion detection capabilities Relevant to TGA medical device regulations for wearable health technologies; potential applications in aged care monitoring and rehabilitation services covered under Medicare Patients requiring wearable health monitoring devices, rehabilitation sensors, and human-machine interface applications

Abstract

Piezoelectric silk fibroin (SF) shows great potential in fabricating sustainable wearable electronics toward health monitoring and human-machine interfacing, yet the processing difficulty and brittleness restrict its practical applications severely. This study proposes a simple strategy to achieve the boosted piezoelectricity and mechanical properties in electrospun regenerated silk fibroin (RSF) nanofiber mats by adding polyethylene glycol (PEG) with different molecular weights to induce the formation of β-sheets via hydrogen bonding and the regulation of PEG phase morphology. Specifically, RSFs consisting of PEG of 2000 and 1000 Da exhibit a significant improvement in the tensile strength (from 6.1 to 9.92 MPa) and elongation at break (from 5.72% to 117.58%), respectively. Meanwhile, RSFs consisting of PEG with a molecular weight of 2000 and 400 Da show a direct piezoelectric force sensitivity of 0.2 mV/N·μm and 0.14 mV/N·μm respectively, superior to that of pure RSF (0.04 mV/N·μm). The piezoelectric force sensors fabricated with RSFs show potential applications in the detection of diverse human motions, including finger tapping for Morse code, grip strength, and knee flexion. Thus, this work unveils a facile strategy to fabricate RSF-based biodegradable piezoelectric force sensors with a trade-off in processability, mechanical ductility, and piezoelectricity.

References

1. 1.Chen, M. H., Hu, Y. D., Wu, Y. J., Guo, J. X., Ke, K., Wang, Y., Yin, B., & Yang, W. (2026). Boosting piezoelectricity and mechanical properties of silk fibroin films via polyethylene glycol phase manipulation. ACS Applied Materials & Interfaces. https://doi.org/10.1021/acsami.6c02587