title: Investigation of a rifampin, fusidic-acid and mupirocin releasing silicone catheter.
abstract: After strict hygienical measures have been exhausted the use of plastic materials with antibacterial activity may reduce catheter related-bacterial colonization. An antimicrobial silicone catheter was investigated by HPLC-measurement, SEM, antimicrobial assays and standard biocompatibility tests. The modified catheter was highly biocompatible and the antimicrobial leaching non-toxic. The initially release rate was governed by the drug solubility in the 'sink' and surface loading ('burst effect'). The second continuous period depended on the drug velocity in the silicone matrix and was extended up to 100 days with a proportionality to square root of t for each drug. Diffusion exponents were in range of 2 x 10(-8) to 1 x 10(-9) (cm2 sec(-1)). The lower diffusion exponent of mupirocin was explained by its higher cohesion energy and lower physico-chemical compatibility with the embedding silicone. The antimicrobial drugs were in a molecular-dispersed state with the silicone-matrix, whereas superficially located crystals of the antibiotics covering the catheter surface could be demonstrated by SEM.
authors.affiliation: Institute of Medical Microbiology and Hygiene, University of Cologne, Germany.
authors.forename: J M
authors.initials: JM
authors.lastname: Schierholz
authors.forename: G
authors.initials: G
authors.lastname: Pulverer
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000737:chemistry / Q000494:pharmacology; D000904:Antibiotics, Antitubercular / Q000008:administration & dosage* / Q000737:chemistry / Q000494:pharmacology; D001422:Bacterial Adhesion; D001672:Biocompatible Materials; D002404:Catheterization / Q000295:instrumentation*; D002557:Cerebrospinal Fluid Shunts / Q000295:instrumentation; D003692:Delayed-Action Preparations; D004912:Erythrocytes / Q000187:drug effects; D005672:Fusidic Acid / Q000008:administration & dosage* / Q000737:chemistry / Q000494:pharmacology; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D008826:Microbial Sensitivity Tests; D008855:Microscopy, Electron, Scanning; D016712:Mupirocin / Q000008:administration & dosage* / Q000737:chemistry / Q000494:pharmacology; D012293:Rifampin / Q000008:administration & dosage* / Q000737:chemistry / Q000494:pharmacology; D012828:Silicones; D013211:Staphylococcus aureus / Q000187:drug effects; D013212:Staphylococcus epidermidis / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D000904:Antibiotics, Antitubercular; D001672:Biocompatible Materials; D003692:Delayed-Action Preparations; D012828:Silicones; D005672:Fusidic Acid; D016712:Mupirocin; D012293:Rifampin