Hydrophilic polymers -: biocompatibility testing in vitro

Biocompatibility is one of the main prerequisites for safe use of medical devices. Estimation of cytotoxicity is a part of the initial evaluation laid down in ISO standards on biological evaluation of medical devices. Hydrophilic polymers (based on 2-hydroxyethyl methacrylate HEMA) doped by addition of selected additives with antioxiclant and/or free radical scavenging potential (vitamin C and hindered amine stabilizer N-(2,2,6,6-tetramethylpiperidin-4-yl)methacrylamide) were tested in different in vitro systems (3T3 Balb/c cell culture and a 3D human skin model) for biocompatibility and suitability for use as wound dressings. The results of the 3T3 NRU cytotoxicity test using both the direct and indirect contact approaches and a 3D skin model modified irritation test (EpiDerm (TM)) confirmed high biocompatibility and good skin tolerance of both the basic polymers and those enriched with specific additives up to a balanced level. HEMA polymer showed a beneficial effect against cytotoxicity of an irritant (sodium dodecyl sulfate). The in vitro biocompatibility test results were confirmed by human local skin tolerance testing. (c) 2005 Elsevier Ltd. All rights reserved.