Piezoelectric properties of collagen films: Insights into their potential for electroactive biomedical applications

Electroactive biomaterials and, in particular, piezoelectric ones are gaining insight into tissue engineering and biomedical applications. Collagen is one of the most available biomaterials found in nature, and the present study focus on the evaluation of its piezoelectric response. Collagen extracted from bovine skin was used and the piezoelectric response was correlated to the physicochemical, thermal, morphological and mechanical properties. A dense fibrillar microstructure was observed and the mechanical properties, which depend on the specific amino acids composition, showed tensile strength and maximum strain values of 34 MPa and 18 %, respectively. Collagen films exhibited approximately 25 % weight loss after 1 day in PBS solution, increasing to about 30 % and 100 % at day 2 and 4, respectively. A piezoelectric response of 0.44 pm/V was obtained, demonstrating the collagen film suitability for electroactive materials in biomedical applications.