title: Versatile and inexpensive Hall-Effect force sensor for mechanical characterization of soft biological materials.
abstract: Mismatch of hierarchical structure and mechanical properties between tissue-engineered implants and native tissue may result in signal cues that negatively impact repair and remodeling. With bottom-up tissue engineering approaches, designing tissue components with proper microscale mechanical properties is crucial to achieve necessary macroscale properties in the final implant. However, characterizing microscale mechanical properties is challenging, and current methods do not provide the versatility and sensitivity required to measure these fragile, soft biological materials. Here, we developed a novel, highly sensitive Hall-Effect based force sensor that is capable of measuring mechanical properties of biological materials over wide force ranges (μN to N), allowing its use at all steps in layer-by-layer fabrication of engineered tissues. The force sensor design can be easily customized to measure specific force ranges, while remaining easy to fabricate using inexpensive, commercial materials. Although we used the force sensor to characterize mechanics of single-layer cell sheets and silk fibers, the design can be easily adapted for different applications spanning larger force ranges (>N). This platform is thus a novel, versatile, and practical tool for mechanically characterizing biological and biomimetic materials.
authors.affiliation: Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA.
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Backman
authors.affiliation: Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA.
authors.forename: Bauer L
authors.initials: BL
authors.lastname: LeSavage
authors.affiliation: Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA; Division of Materials Science & Engineering, Boston University, Boston, MA 02215, USA. Electronic address: jywong@bu.edu.
authors.forename: Joyce Y
authors.initials: JY
authors.lastname: Wong
mesh_terms: D000818:Animals; D040761:Biomimetic Materials; D002417:Cattle; D002478:Cells, Cultured; D055595:Mechanical Phenomena; D032389:Myocytes, Smooth Muscle / Q000502:physiology*; D019736:Prostheses and Implants; D047011:Silk / Q000502:physiology*; D023822:Tissue Engineering
chemical_list: D047011:Silk
keywords: Cell sheet mechanics; Force sensor; Hall-Effect; Silk fiber mechanics