【国外标准】 Standard Practice for Direct Contact Cell Culture Evaluation of Materials for Medical Devices

4.1 This practice is useful for assessing cytotoxic potential both when evaluating new materials or formulations for possible use in medical applications, and as part of a quality control program for established medical materials and medical devices.4.2 This practice assumes that assessment of cytotoxicity potential provides one method for predicting the potential for cytotoxic or necrotic reactions to medical materials and devices during clinical applications to humans. In general, cell culture testing methods have shown good correlation with animal assays when only chemical toxicities are being considered.NOTE 1: The results obtained using this method may not predict in vivo behavior which can be influenced by multiple factors such as those arising from site of application or physical properties that may result from design and fabrication.4.3 This cell culture test method is suitable for adoption in specifications and standards for materials for use in the construction of medical devices that are intended to have direct contact with tissue, tissue fluids, or blood. However, care should be taken when testing materials that are absorbable, include an eluting or degradable coating, are liquid or gelatinous in nature, are irregularly shaped solid materials, or have a high density or mass, to make sure that the method is applicable. If leachables from the test sample are capable of diffusing through the agar layer, agarose-based methods such as Test Method F895 may be considered as an alternate method, depending on sample characteristics, or in cases where investigators wish to further evaluate the cytotoxic response of cells underlying the test sample.1.1 This practice covers a reference method of direct contact cell culture testing which may be used in evaluating the cytotoxic potential of materials for use in the construction of medical materials and devices.1.2 This practice may be used either directly to evaluate materials or as a reference against which other cytotoxicity test methods may be compared.1.3 This is one of a series of reference test methods for the assessment of cytotoxic potential, employing different techniques.1.4 Assessment of cytotoxicity is one of several tests employed in determining the biological response to a material, as recommended in Practice F748.1.5 The L-929 cell line was chosen because it has a significant history of use in assays of this type. This is not intended to imply that its use is preferred; only that the L-929 is a well characterized, readily available, established cell line that has demonstrated reproducible results in several laboratories.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.