title: Controlled-Potential Electromechanical Reshaping of Cartilage.
abstract: An alternative to conventional "cut-and-sew" cartilage surgery, electromechanical reshaping (EMR) is a molecular-based modality in which an array of needle electrodes is inserted into cartilage held under mechanical deformation by a jig. Brief (ca. 2 min) application of an electrochemical potential at the water-oxidation limit results in permanent reshaping of the specimen. Highly sulfated glycosaminoglycans within the cartilage matrix provide structural rigidity to the tissue through extensive ionic-bonding networks; this matrix is highly permselective for cations. Our studies indicate that EMR results from electrochemical generation of localized, low-pH gradients within the tissue: fixed negative charges in the proteoglycan matrix are protonated, resulting in chemically induced stress relaxation of the tissue. Re-equilibration to physiological pH restores the fixed negative charges, and yields remodeled cartilage that retains a new shape approximated by the geometry of the reshaping jig.
authors.affiliation: Department of Chemistry and Chemical Biology, Occidental College, Los Angeles, CA, 90041, USA.
authors.forename: Bryan M
authors.initials: BM
authors.lastname: Hunter
authors.affiliation: Department of Chemistry and Chemical Biology, Occidental College, Los Angeles, CA, 90041, USA.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Kallick
authors.affiliation: Department of Chemistry and Chemical Biology, Occidental College, Los Angeles, CA, 90041, USA.
authors.forename: Jessica
authors.initials: J
authors.lastname: Kissel
authors.affiliation: Department of Chemistry and Chemical Biology, Occidental College, Los Angeles, CA, 90041, USA.
authors.forename: Maya
authors.initials: M
authors.lastname: Herzig
authors.affiliation: Department of Chemistry and Chemical Biology, Occidental College, Los Angeles, CA, 90041, USA.
authors.forename: Cyrus
authors.initials: C
authors.lastname: Manuel
authors.affiliation: The Beckman Laser Institute and Medical Clinic, University of California, Irvine, USA.
authors.forename: Dmitri
authors.initials: D
authors.lastname: Protsenko
authors.affiliation: The Beckman Laser Institute and Medical Clinic, University of California, Irvine, USA.|Department of Otolaryngology-Head and Neck Surgery, University of California, Irvine, USA.|Department of Biomedical Engineering, University of California, Irvine, USA.
authors.forename: Brian J F
authors.initials: BJ
authors.lastname: Wong
authors.affiliation: Department of Chemistry and Chemical Biology, Occidental College, Los Angeles, CA, 90041, USA. mgh@oxy.edu.
authors.forename: Michael G
authors.identifier: 0000-0002-9085-7141
authors.initials: MG
authors.lastname: Hill
mesh_terms: D002356:Cartilage / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000295:instrumentation; D004566:Electrodes; D006863:Hydrogen-Ion Concentration
keywords: cartilage; chemical stress relaxation; electrochemistry; electromechanical reshaping; permselectivity