Inappropriate activation of complement by blood-contacting medical devices may have serious acute or chronic effects on the host. Solid medical device materials may activate the complement directly by the alternative pathway. Unlike the classical complement activation pathway (see Practice F1984), antibodies are not required for alternative pathway activation. This practice is useful as a simple, inexpensive screening method for determining alternative whole complement activation by solid materials in vitro.This practice is composed of two parts. In Part A (Section 10) C4(-)GPS is exposed to a solid material. Since C4 is required for classical pathway activation, activation of complement in C4(-)GPS can only occur by the alternative pathway (1). In principle, nonspecific binding of certain complement components to the materials may also occur. In Part B (Section 11), complement activity remaining in the serum after exposure to the test material is assayed by alternative pathway-mediated lysis of rabbit RBC.Assessment of in vitro whole complement activation as described here provides one method for predicting potential complement activation by solid medical device materials intended for clinical application in humans when the material contacts the blood. Other test methods for complement activation are available, including assays for specific complement components and their split products in human serum (X1.3 and X1.4).This in vitro test method is suitable for adoption in specifications and standards for screening solid materials for use in the construction of medical devices intended to be implanted in the human body or placed in contact with human blood outside the body.1.1 This practice provides a protocol for rapid, in vitro screening for alternative pathway complement activating properties of solid materials used in the fabrication of medical devices that will contact blood.1.2 This practice is intended to evaluate the acute in vitro alternative pathway complement activating properties of solid materials intended for use in contact with blood. For this practice, “serum” is synonymous with “complement.”1.3 This practice consists of two procedural parts. Procedure A describes exposure of solid materials to a standard lot of C4-deficient guinea pig serum [C4(-)GPS], using 0.1-mL serum per 13 × 100-mm disposable glass test tubes. Sepharose CL-4B is used as an example of test materials. Procedure B describes assaying the exposed serum for significant functional alternative pathway complement depletion as compared to control samples. The endpoint in procedure B is lysis of rabbit RBC in buffer containing EGTA and excess Mg++.1.4 This practice does not address function, elaboration, or depletion of individual complement components except as optional additional confirmatory information that can be acquired using human serum as the complement source. This practice does not address the use of plasma as a source of complement.1.5 This practice is one of several developed for the assessment of the biocompatibility of materials. Practice F748 may provide guidance for the selection of appropriate methods for testing materials for other aspects of biocompatibility. Practice F1984 provides guidance for testing solid materials for whole complement activation in human serum, but does not discriminate between the classical or alternative pathway of activation.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

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5.1 Bonding of many polymeric substrates presents a problem due to the low wettability of their surfaces and their chemical inertness. Adhesive bond formation begins with the establishment of interfacial molecular contact by wetting. Wettability of a substrate surface depends on its surface energy. The surface activation with electrical discharges improves wettability of polymers and subsequent adhesive bonding. The surface activation with electrical discharges results in addition of polar functional groups on the polymer surface. The higher the concentration of polar functional groups on the surface the more actively the surface reacts with the different polar interfaces.5.2 To achieve a proper adhesive bond the polyolefin substrate's polar component should be raised from near zero to 15 to 20 mJ/m2.5.3 The pre-treated surfaces are ready for application of the adhesive immediately after the treatment.1.1 This practice covers various electrical discharge treatments to be used to enhance the ability of polymeric substrates to be adhesively bonded. This practice does not include additional information on the preparation of test specimens or testing conditions as they are covered in the various ASTM test methods or specifications for specific materials.1.2 The types of discharge phenomena that are used for surface modification of polymers fit into the general category of nonequilibrium or non-thermal discharges in which electron temperature (mean energy) greatly exceeds the gas temperature.1.3 The technologies included in this practice are:Technology SectionGas plasma at reduced pressure 8Electrical discharges at atmospheric pressure 9AC dielectric barrier discharge 9.1High Frequency Apparatus 9.1.1Suppressed Spark Apparatus 9.1.2Arc Plasma Apparatus 9.2Glow Discharge Apparatus 9.3NOTE 1: The term “corona treatment” has been applied sometimes in the literature to the different electrical discharge treatment technologies described in Section 9. This practice defines each electrical discharge treatment technology at atmospheric pressure presented in Section 9 and draws the necessary distinctions between them and corona discharge. See Test Method D1868 for “corona discharge.”1.4 The values stated in SI units are to be regarded as the standard.1.5 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. Specific hazard statements appear in Section 6.1.6 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.

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4.1 The activation spectrum identifies the spectral region(s) of the specific exposure source used that may be primarily responsible for changes in appearance and/or physical properties of the material.4.2 The spectrographic technique uses a prism or grating spectrograph to determine the effect on the material of isolated narrow spectral bands of the light source, each in the absence of other wavelengths.4.3 The sharp cut-on filter technique uses a specially designed set of sharp cut-on UV/visible transmitting glass filters to determine the relative actinic effects of individual spectral bands of the light source during simultaneous exposure to wavelengths longer than the spectral band of interest.4.4 Both the spectrographic and filter techniques provide activation spectra, but they differ in several respects:4.4.1 The spectrographic technique generally provides better resolution since it determines the effects of narrower spectral portions of the light source than the filter technique.4.4.2 The filter technique is more representative of the polychromatic radiation to which samples are normally exposed with different, and sometimes antagonistic, photochemical processes often occurring simultaneously. However, since the filters only transmit wavelengths longer than the cut-on wavelength of each filter, antagonistic processes by wavelengths shorter than the cut-on are eliminated.4.4.3 In the filter technique, separate specimens are used to determine the effect of the spectral bands and the specimens are sufficiently large for measurement of both mechanical and optical changes. In the spectrographic technique, except in the case of spectrographs as large as the Okazaki type (1),4 a single small specimen is used to determine the relative effects of all the spectral bands. Thus, property changes are limited to those that can be measured on very small sections of the specimen.4.5 The information provided by activation spectra on the spectral region of the light source responsible for the degradation in theory has application to stabilization as well as to stability testing of polymeric materials (2).4.5.1 Activation spectra based on exposure of the unstabilized material to solar radiation identify the light screening requirements and thus the type of ultraviolet absorber to use for optimum screening protection. The closer the match of the absorption spectrum of a UV absorber to the activation spectrum of the material, the more effective the screening. However, a good match of the UV absorption spectrum of the UV absorber to the activation spectrum does not necessarily assure adequate protection since it is not the only criteria for selecting an effective UV absorber. Factors such as dispersion, compatibility, migration and others can have a significant influence on the effectiveness of a UV absorber (see Note 3). The activation spectrum must be determined using a light source that simulates the spectral power distribution of the one to which the material will be exposed under use conditions.NOTE 3: In a study by ASTM G03.01, the activation spectrum of a copolyester based on exposure to borosilicate glass-filtered xenon arc radiation predicted that UV absorber A would be superior to UV absorber B in outdoor use because of stronger absorption of the harmful wavelengths of solar simulated radiation. However, both additives protected the copolyester to the same extent when exposed either to xenon arc radiation or outdoors.4.5.2 Comparison of the activation spectrum of the stabilized with that of the unstabilized material provides information on the completeness of screening and identifies any spectral regions that are not adequately screened.4.5.3 Comparison of the activation spectrum of a material based on solar radiation with those based on exposure to other types of light sources provides information useful in selection of the appropriate artificial test source. An adequate match of the harmful wavelengths of solar radiation by the latter is required to simulate the effects of outdoor exposure. Differences between the natural and artificial source in the wavelengths that cause degradation can result in different mechanisms and type of degradation.4.5.4 Published data have shown that better correlations can be obtained between natural weathering tests under different seasonal conditions when exposures are timed in terms of solar UV radiant exposure only rather than total solar radiant exposure. Timing exposures based on only the portion of the UV identified by the activation spectrum to be harmful to the material can further improve correlations. However, while it is an improvement over the way exposures are currently timed, it does not take into consideration the effect of moisture and temperature.4.6 Over a long test period, the activation spectrum will register the effect of the different spectral power distributions caused by lamp or filter aging or daily or seasonal variation in solar radiation.4.7 In theory, activation spectra may vary with differences in sample temperature. However, similar activation spectra have been obtained at ambient temperature (by the spectrographic technique) and at about 65 °C (by the filter technique) using the same type of radiation source.1.1 This practice describes the determination of the relative actinic effects of individual spectral bands of an exposure source on a material. The activation spectrum is specific to the light source to which the material is exposed to obtain the activation spectrum. A light source with a different spectral power distribution will produce a different activation spectrum.1.2 This practice describes two procedures for determining an activation spectrum. One uses sharp cut-on UV/visible transmitting filters and the other uses a spectrograph to determine the relative degradation caused by individual spectral regions.NOTE 1: Other techniques can be used to isolate the effects of individual spectral bands of a light source, for example, interference filters.1.3 The techniques are applicable to determination of the spectral effects of solar radiation and laboratory accelerated test devices on a material. They are described for the UV region, but can be extended into the visible region using different cut-on filters and appropriate spectrographs.1.4 The techniques are applicable to a variety of materials, both transparent and opaque, including plastics, paints, inks, textiles and others.1.5 The optical and/or physical property changes in a material can be determined by various appropriate methods. The methods of evaluation are beyond the scope of this practice.1.6 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.NOTE 2: There is no ISO standard that is equivalent to this standard.1.7 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.

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5.1 High levels of antimony are commonly used in flame retardant formulations for various materials. NAA is a test method that can be useful for verifying these levels and, for other materials, NAA can also be useful in establishing the amount of low level contamination, if any, with high sensitivity and high precision.5.2 Neutron activation analysis provides a rapid, highly sensitive, nondestructive procedure for antimony determination in a wide range of matrices. This test method is independent of the chemical form of the antimony.5.3 This test method can be used for quality and process control in the petrochemical and other manufacturing industries, and for research purposes in a broad spectrum of applications.1.1 This test method covers the measurement of antimony concentration in plastics or other hydrocarbon or organic matrix by using neutron activation analysis (NAA). The sample is activated by irradiation with neutrons from a research reactor and the subsequently emitted gamma-rays are detected with a germanium semiconductor detector. The same system may be used to determine antimony concentrations ranging from 1 ng/g to 10 000 μg/g with the lower end of the range limited by numerous interferences and the upper limit established by the demonstrated practical application of NAA.1.2 This test method may be used on either solid or liquid samples, provided that they can be made to conform in size and shape during irradiation and counting to a standard sample of known antimony content using very simple sample preparation. Several variants of this method have been described in the technical literature. A monograph is available which provides a comprehensive description of the principles of neutron activation analysis using reactor neutrons (1).21.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 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. Specific precautions are given in Section 9.1.5 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.

定价： 590元 / 折扣价： 502 元 加购物车

Inappropriate activation of complement by blood-contacting medical devices may have serious acute or chronic effects on the host. Solid medical device materials may activate complement directly by the alternative pathway, or indirectly because of antigen-bound antibodies (as with immuno-adsorption columns) by the classical pathway. This practice is useful as a simple, inexpensive, function-based screening method for determining complement activation by solid materials in vitro by the classical pathway.This practice is composed of two parts. In part A (Section 11), HS is exposed to a solid material. If complement activation occurs by the classical pathway, C4 will be depleted. Activation by the alternative pathway will not deplete C4. In part B (Section 12), C4 activity remaining in the serum after exposure to the test material is assayed by diluting the serum below the concentration needed to lyse antibody-coated sheep RBC on its own, then adding the diluted HS to C4(-)GPS (which is itself at a dilution where all complement components are in excess save the missing C4). Lacking C4, the C4(-)GPS does not lyse the antibody-coated sheep RBC unless C4 is present in the added HS. The proportion of lysis remaining in the material-exposed HS sample versus the 37°C control HS sample (which was not exposed to the test material) indicates the amount of C4 present in the HS, loss of which correlates with classical pathway activation.This function-based in vitro test method for classical pathway complement activation is suitable for adoption in specifications and standards for screening solid materials for use in the construction of medical devices intended to be implanted in the human body or placed in contact with human blood outside the body. It is designed to be used in conjunction with Practice F1984 for function-based whole complement activation screening, and Practice F2065 for function-based alternative pathway activation screening.Assessment of in vitro classical complement activation as described here provides one method for predicting potential complement activation by solid medical device materials intended for clinical application in humans when the material contacts the blood. Other test methods for complement activation are available, such as immunoassays for specific complement components (including C4) and their split products in human serum (see X1.3 and X1.4).If nonspecific binding of certain complement components, including C4, to the materials occurs in part A of this practice, a false positive for classical pathway activation will be observed in step B. Classical pathway complement activation by the test material may be confirmed by demonstrating an absence of C4 bound to the material following removal of the serum, and/or production of complement split-products such as C4d in the serum (as determined by immunoassay). Although immunoassay could be done in place of this screening procedure, determination of C4d production alone may not be functionally significant. This practice does not detect trivial amounts of classical activation unable to affect functional lysis of sensitized RBC.1.1 This practice provides a protocol for rapid, in vitro functional screening for classical pathway complement activating properties of solid materials used in the fabrication of medical devices that will contact blood.1.2 This practice is intended to evaluate the acute in vitro classical pathway complement activating properties of solid materials intended for use in contact with blood. For this practice, “serum” is synonymous with “complement.”1.3 This practice consists of two procedural parts. Procedure A describes exposure of solid materials to a standard lot of human serum [HS], using 0.1 mL serum per 13×100 mm disposable glass test tube. Procedure B describes assaying the exposed serum for significant functional classical pathway complement depletion (decrease in amount of C4) as compared to control serum samples not exposed to the material. The endpoint in Procedure B is lysis of sheep red blood cells (RBC) coated with antibody (hemolysin).1.4 This practice does not address the use of plasma as a source of complement.1.5 This practice is one of several developed for the assessment of the biocompatibility of materials. Practice F748 may provide guidance for the selection of appropriate methods for testing materials for other aspects of biocompatibility. Practice F1984 provides guidance for testing solid materials for whole complement activation in human serum, but does not discriminate between the classical or alternative pathway of activation. Practice F2065 provides guidance for testing solid materials for alternative pathway complement activation in serum.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 and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 The conventional determination of oxygen content in liquid or solid samples is a relatively difficult chemical procedure. It is slow and usually of limited sensitivity. The 14-MeV neutron activation and direct counting technique provides a rapid, highly sensitive, nondestructive procedure for oxygen determination in a wide range of matrices. This test method is independent of the chemical form of the oxygen.5.2 This test method can be used for quality and process control in the metals, coal, and petroleum industries, and for research purposes in a broad spectrum of applications.1.1 This test method covers the measurement of oxygen concentration in almost any matrix by using a 14-MeV neutron activation and direct-counting technique. Essentially, the same system may be used to determine oxygen concentrations ranging from under 10 μg/g to over 500 mg/g, depending on the sample size and available 14-MeV neutron fluence rates.NOTE 1: The range of analysis may be extended by using higher neutron fluence rates, larger samples, and higher counting efficiency detectors.1.2 This test method may be used on either solid or liquid samples, provided that they can be made to conform in size, shape, and macroscopic density during irradiation and counting to a standard sample of known oxygen content. Several variants of this method have been described in the technical literature. A monograph is available which provides a comprehensive description of the principles of activation analysis using a neutron generator (1).21.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 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.Specific precautions are given in Section 8.1.5 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.

定价： 590元 / 折扣价： 502 元 加购物车

5.1 Inappropriate activation of complement by blood-contacting medical devices may have serious acute or chronic effects on the host. This practice is useful as a simple, inexpensive screening method for determining functional whole complement activation by solid materials in vitro.5.2 This practice is composed of two parts. In Part A (Section 11), human serum is exposed to a solid material. Complement may be depleted by the classical or alternative pathways. In principle, nonspecific binding of certain complement components also may occur. The alternative pathway can deplete later acting components common to both pathways, that is components other than C1, C4, and C3 (1) .4 In Part B (Section 12), complement activity remaining in the serum after exposure to the test material is assayed by classical pathway-mediated lysis of sensitized RBC.5.3 Assessment of in vitro whole complement activation, as described here, provides one method for predicting potential complement activation by medical materials intended for clinical application in humans when the material contacts the blood. Other test methods for complement activation are available, including assays for specific complement components and their split products (see X1.3 and X1.4).5.4 This in vitro test method is suitable for adoption in specifications and standards for screening solid materials for use in the construction of medical devices intended to be implanted in the human body or placed in contact with human blood.1.1 This practice provides a protocol for rapid, in vitro screening for whole complement activating properties of solid materials used in the fabrication of medical devices that will contact blood.1.2 This practice is intended to evaluate the acute in vitro whole complement activating properties of solid materials intended for use in contact with blood. For this practice, the words “serum” and “complement” are used interchangeably (most biological supply houses use these words synonymously in reference to serum used as a source of complement).1.3 This practice consists of two procedural parts. Procedure A describes exposure of solid materials to a standard lot of human serum, using a 0.1-mL serum/13 x 100-mm disposable test tube. Cellulose acetate powders and fibers are used as examples of test materials. Procedure B describes assaying the exposed serum for significant functional whole complement depletion as compared to control samples.1.4 This practice does not address function, elaboration, or depletion of individual complement components, nor does it address the use of plasma as a source of complement.1.5 This practice is one of several developed for the assessment of the biocompatibility of materials. Practice F748 may provide guidance for the selection of appropriate methods for testing materials for other aspects of biocompatibility.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 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.

定价： 590元 / 折扣价： 502 元 加购物车