ASTM_E_2180_-_07_2012.pdf

Designation:E218007(Reapproved 2012)Standard Test Method forDetermining the Activity of Incorporated AntimicrobialAgent(s)In Polymeric or Hydrophobic Materials1This standard is issued under the fixed designation E2180;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.INTRODUCTIONPolymeric materials such as vinyl pool liners,shower curtains,and various medical devices aretreated frequently with incorporated or bound antimicrobial agents.Practices G21 is used to determinethe ability of polymer materials to resist microbial attack or staining(see also Practice E1428);however,none of the methods permit quantitative evaluations of incorporated antimicrobial activity.2These antimicrobials typically require contact with the microbial cell for maximal activity.Whenaqueous based bacterial inoculum suspensions are applied onto a preservative-treated plastic or otherhydrophobic material,the surface tension of the polymer often causes the inocula suspension to dome.Bacteria within the drops of inoculum may not contact the treated surface if the challenged surfacedoes not dry,or upon drying,cells may become layered.This test standard involves an agar slurryinoculum vehicle that provides a relatively uniform contact of the inocula with antimicrobial-treatedhydrophobic surfaces.1.Scope1.1 This test method is designed to evaluate(quantitatively)the antimicrobial effectiveness of agents incorporated or boundinto or onto mainly flat(two dimensional)hydrophobic orpolymeric surfaces.The method focuses primarily on assessingantibacterial activity;however,other microorganisms such asyeast and fungal conidia may be tested using this method.1.2 The vehicle for the inoculum is an agar slurry whichreduces the surface tension of the saline inoculum carrier andallows formation of a“pseudo-biofilm,”providing more evencontact of the inoculum with the test surface.NOTE1This test method facilitates the testing of hydrophobicsurfaces by utilizing cells held in an agar slurry matrix.This test method,as written,is inappropriate to determine efficacy against biofilm cells,which are different both genetically and metabolically than planktoniccells used in this test.1.3 This method can confirm the presence of antimicrobialactivity in plastics or hydrophobic surfaces and allows deter-mination of quantitative differences in antimicrobial activitybetween untreated plastics or polymers and those with boundor incorporated low water-soluble antimicrobial agents.Com-parisons between the numbers of survivors on preservative-treated and control hydrophobic surfaces may also be made.1.4 The procedure also permits determination of“shelf-life”or long term durability of an antimicrobial treatment whichmay be achieved through testing both non-washed and washedsamples over a time span.1.5 Knowledge of microbiological techniques is requiredfor these procedures.1.6 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.7 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility 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:3E1054 Test Methods for Evaluation of Inactivators of Anti-microbial Agents1This test method is under the jurisdiction of ASTM Committee E35 onPesticides,Antimicrobials,and Alternative Control Agents and is the directresponsibility of Subcommittee E35.15 on Antimicrobial Agents.Current edition approved April 1,2012.Published June 2012.Originallyapproved in 2001.Last previous edition approved in 2007 as E2180 07.DOI:10.1520/E2180-07R12.2Price,D.L.,Sawant,A.D.,and Ahearn,D.G.,“Assessment of the antimicro-bial activity of an insoluble quaternary amine complex in plastics,”J.Industr.Microbiol,Vol 8,No.2,1991,pp.8389.3For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 E1428 Test Method for Evaluating the Performance ofAntimicrobials in or on Polymeric SolidsAgainst Stainingby Streptoverticillium reticulum(A Pink Stain Organism)G21 Practice for Determining Resistance of Synthetic Poly-meric Materials to Fungi3.Terminology3.1 Definitions:3.1.1 agar slurry,na semi-gelatinous liquid formed when3 g/L agar-agar is added to a 0.85%saline solution.3.1.2 inoculum vehicle,nthe carrier solution used totransport bacterial cells to a test surface.Samples inclu