title: Characteristics, interactions and coating adherence of heterogeneous polymer/drug coatings for biomedical devices.
abstract: With this rise in surgical procedures it is important to focus on the mobility and safety of the patient and reduce the infections that are associated with hip replacements. We examine the mechanical properties of gentamicin sulphate as a model antimicrobial layer for titanium-alloy based prosthetic hips to help prevent methicillin-resistant Staphylococcus aureus infection after surgery. A top layer of poly(lactic-co-glycolic acid) is added to maintain the properties of the gentamicin sulphate as well as providing a drug delivery system. Through the use of nanoindentation and micro-scratch techniques it is possible to determine the mechanical and adhesive properties of this system. Nanoindentation determined the modulus values for the poly(lactic-co-glycolic acid) and gentamicin sulphate materials to be 8.9 and 5.2GPa, respectively. Micro-scratch established that the gentamicin sulphate layer is strongly adhered to the Ti alloy and forces of 30N show no cohesive or adhesive failure. It was determined that the poly(lactic-co-glycolic acid) is ductile in nature and delaminates from the gentamicin sulphate layer of at 0.5N.
authors.affiliation: Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2, Ireland.
authors.forename: Colm
authors.initials: C
authors.lastname: McManamon
authors.affiliation: Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2, Ireland; School of Physics, Trinity College Dublin, Dublin 2, Ireland.
authors.forename: Johann P
authors.initials: JP
authors.lastname: de Silva
authors.affiliation: Department of Chemistry, Supercritical Fluid Centre and Materials Section, University College Cork, Cork, Ireland.
authors.forename: Paul
authors.initials: P
authors.lastname: Delaney
authors.affiliation: Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2, Ireland; Department of Chemistry, Supercritical Fluid Centre and Materials Section, University College Cork, Cork, Ireland.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Morris
authors.affiliation: Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2, Ireland; School of Physics, Trinity College Dublin, Dublin 2, Ireland. Electronic address: crossg@tcd.ie.
authors.forename: Graham L W
authors.initials: GLW
authors.lastname: Cross
mesh_terms: D000497:Alloys / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000737:chemistry / Q000494:pharmacology; D005839:Gentamicins / Q000737:chemistry / Q000494:pharmacology; D006622:Hip Prosthesis; D006801:Humans; D019344:Lactic Acid / Q000737:chemistry / Q000494:pharmacology; D055624:Methicillin-Resistant Staphylococcus aureus / Q000254:growth & development*; D011100:Polyglycolic Acid / Q000737:chemistry / Q000494:pharmacology; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D014025:Titanium / Q000737:chemistry*
chemical_list: D000497:Alloys; D020099:Coated Materials, Biocompatible; D005839:Gentamicins; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D014025:Titanium
keywords: Adhesion; Gentamicin; PLGA; Prosthetic hip