1、Designation: D 4200 82 (Reapproved 2003)Standard Test Method forEvaluating Inhibitory Effects of Ink Grids on MembraneFilters1This standard is issued under the fixed designation D 4200; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio
2、n, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method describes a procedure whereby the userof ink-gridded membrane filters in water qualit
3、y studies canascertain whether or not the grid lines are toxic and inhibitoryto bacterial growth when the membrane and its entrappedbacteria are incubated on a suitable media.1.2 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibi
4、lity of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 1129 Terminology Relating to WaterD 1193 Specification for Reagent Water3. Terminology3.1 Defin
5、itionsFor definitions of terms used in this testmethod, refer to Terminology D 1129.4. Summary of Test Method4.1 A heavy bacterial suspension is filtered through agridded membrane filter. The bacterial concentration employedis sufficient to cover much of the membrane with bacterialcolonies.4.2 After
6、 filtration the membrane is incubated on a suitablemedium and the distribution of the colonies and shape of thecolonies noted in the area around each grid line.5. Significance and Use5.1 This test method may be applied to determine thesuitability of grid-marked membrane filters for use in bacte-riol
7、ogical culture techniques for the detection and enumerationof bacterial organisms.5.2 A particularly sensitive organism and growth conditionshave been selected for this test method in order to maximizesensitivity to toxic materials possibly present in the inks usedfor grid-marking membrane filters.6
8、. Apparatus6.1 Incubator, capable of maintaining temperatures of44.56 0.2C.6.2 Membrane Filtration Units.6.3 Vacuum Source with trap vessel.6.4 Forceps, blunt-nosed.6.5 Autoclave or other sterilizing equipment.6.6 Expendables:6.6.1 Gridded membrane filters.6.6.2 1-mL and 10-mL pipets.6.6.3 Petri dis
9、hes (50-mm) containing 6 to 8 mL of agarmedium or a 100-mm dish with 20 6 2 mL of agar medium, orboth.6.6.4 Erlenmeyer flasks.7. Reagents and Materials7.1 Purity of WaterUnless otherwise indicated, referenceto water shall be understood to mean reagent water conformingto reagent water Type II of Spec
10、ification D 1193.7.2 M-FC Agar with Rosolic Acid or equivalent (henceforthreferred to as agar medium), formulated, prepared, and dis-pensed in accordance with the manufacturers specifications.7.3 Tryptone Soya Broth or equivalent (henceforth referredto as broth medium), formulated, prepared, and dis
11、pensed inaccordance with the manufacturers specifications.7.4 Peptone Water, 0.1 %, sterile.7.5 Broth Culture of E. coli ATCC 11229, 18-h, prepared asfollows: Add 1 mL of an 18 6 2-h broth culture of E. coliATCC 11229 to 99 mL of 0.1 % peptone water, mix thor-oughly, then add 0.1 mL of this suspensi
12、on to another flaskcontaining 99 mL of 0.1 % peptone water. This is the workingconcentration and should contain approximately 103bacteriaper millilitre to provide contiguous but discrete growth.1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the direct responsibility
13、 of Subcommittee D19.08 on Membranes and IonExchange Materials.Current edition approved Oct. 29, 1982. Published March 1983.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, r
14、efer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.NOTE 1Hydrophobic leaching may cause growth inhibition in areasadjacent to grid lines.8. Procedure8.1 Assemble the sterile
15、 membrane filtration apparatus, andconnect to vacuum trap and vacuum source.8.2 Process five randomly selected membrane filters, using1-mL aliquots of culture suspension from 7.5, and 30 mL of0.1 % peptone water added to the filter funnel with standardmembrane filtration procedures. Place the membra
16、nes in petridishes containing M-FC agar medium and incubate at 44.5Cfor at least 18 h.8.3 After incubation, examine the overgrown membrane forinhibition of growth along the grid lines.8.4 Examine the membrane filter for growth of “squarecolonies.” The growth of square colonies flowing along gridline
17、s is not necessarily an indication of toxicity, but could be anindication of either compression of the membrane or pluggingof the pores, thus inhibiting nutrient feed to the colonies (seeNote 1).8.5 In this test method, toxicity is defined as the lack ofgrowth in the area immediately adjacent to the
18、 grid lines, andif this effect is noted, repeat the test and if still present, rejectthe membrane filters.9. Precision and Bias9.1 Since this is a qualitative test method, precision and biasstatements are not applicable.10. Keywords10.1 bacterial; filter; inhibitory ink; membraneASTM International t
19、akes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own
20、responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addr
21、essed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at
22、the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 4200 82 (2003)2
