ASTM E787-81 (Reapproved 2017)

Designation: E787 − 81 (Reapproved 2017)Standard Specification forDisposable Glass Micro Blood Collection Pipets1This standard is issued under the fixed designation E787; 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.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 This specification covers two dimensionally differentdisposable glass micropipets used primarily to collect wholehuman blood specimens for clinical analysis and testing. Theyare available as coated with heparin or uncoated.2. Referenced Documents2.1 ASTM Standards:2E438 Specification for Glasses in Laboratory Apparatus3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 disposable micropipets—in accordance with thisspecification and the expected product performance expressedin this standard, those pipets which are to be used one timeonly. Any institution or individual who reuses a disposablepipet must bear full responsibility for its safety and effective-ness.4. Classification4.1 This specification covers two dimensionally differentdisposable glass pipets as follows:4.1.1 Short Pipet—Approximately 75 mm long and coatedwith heparin (Type I) or uncoated (Type II). These arecommercially recognized as Caraway pipets.34.1.2 Long Pipet—Approximately 150 mm long and coatedwith heparin (Type I) or uncoated (Type II). These arecommercially recognized as Natelson pipets.45. Materials and Manufacture5.1 Glass—The pipets shall be fabricated from borosilicateglass, Type I, Class B, or soda lime glass, Type II, inaccordance with Specification E438.5.2 Heparin—shall be the ammonium salt isolated from thelungs or intestinal mucosa of beef or pork origin. The heparinpotency shall be 1 mg of ammonium heparin compound whichis equal to at least 100 USP units.56. Physical Requirements6.1 Design—The disposable glass micro blood collectionpipets, both short and long, shall be straight and pulled to atapered point at one end. Any cross section of the pipets, takenin a plane perpendicular to the longitudinal axis, shall becircular. The pipets shall be lightly firepolished at both endswith no run-in and possess color bands to denote presence orabsence of heparin content.6.2 Dimensions:6.2.1 The short Caraway pipet shall be approximately 75mm long and 4 mm in outside diameter. The pipet shall hold aliquid volume of 310 to 470 µL. The tapered point length andtip orifice opening shall be as specified in Fig. 1.6.2.2 The long Natelson pipet shall be approximately 150mm long and 3 mm in outside diameter. The pipet shall hold aliquid volume of 220 to 420 µL. The tapered point length andtip orifice opening shall be as specified in Fig. 2.6.3 Workmanship—The pipets, as illustrated in Fig. 1 andFig. 2, shall be free of defects that noticeably detract from theirappearance or impair their serviceability. They shall be free oflint, or significant foreign matter, loose or embedded whenviewed under normal room lighting. The top and tip ends of thepipets shall be cut at approximately 90° to the pipet axis andshall not be cracked or have jagged ends or chips that enter thebore of the pipet.6.4 Color Coding—Each disposable glass micro blood col-lection pipet shall be color-coded to identify the pipet. Theheparin-coated pipet (Type 1) shall have a red color band. The1This specification is under the jurisdiction of ASTM Committee E41 onLaboratory Apparatus and is the direct responsibility of Subcommittee E41.01 onLaboratory Ware and Supplies.Current edition approved Jan. 1, 2017. Published February 2017. Originallyapproved in 1981. Last previous edition approved in 2011 as E787 – 81 (2011).DOI: 10.1520/E0787-81R17.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at service@astm.org. For Annual Book of ASTMStandards volume information, refer to the standard’s Document Summary page onthe ASTM website.3Caraway, W. T., and Fanger, H., “Ultramicro Procedures In ClinicalChemistry,” American Journal of Clinical Pathology , 25, 1955, pp. 316–331.4Natelson, S., Ph.D., Micro-Techniques of Clinical Chemistry, Charles C.Thomas, Springfield, Ill., 1961, p. 70.5The United States Pharmacopeia, 19th Revision, pp. 229–230.Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1uncoated pipet (Type 2) shall have a blue color band. Thelocation of these color bands shall be as specified in Fig. 1 andFig. 2.6.5 Capillary—The pipets, both short and long, shall becapable of drawing sheep plasma or human whole blood thefull length of the pipet when tested as specified in 7.1.6.6 Fluidity (Type 1, Heparinized, only)—Coagulation ofthe sheep plasma or human whole blood shall not be evidentwhen viewed under normal room lighting and tested asspecified in 7.2.6.7 Lot or Control Number—A lot or control number shallbe indicated on the intermediate and outer package of pipets.This lot or control number shall be traceable to the origin (rawmaterial glass and heparin purchases) of the manufacturingrecord.6.8 Resistance to Centrifugal Forces— The pipets, bothshort and long, may be subject to centrifugal force undernormal analysis or test procedures. No breakage shall resultwhen tested as specified in 7.3.6.9 Heparin Coating (Type 1, Heparinized, only)—Theinner surface of the short and long pipets shall be evenly coatedwith ammonium heparin. A minimum of 5.0 units of heparinactivity shall be present in the tube when tested as specified in6.4. A statement on expected units of heparin and an expirationdate may be claimed by the manufacturer. This option may beexpressed on the pipet package label.7. Test Methods7.1 Capillarity Test—Test the pipets, both short and long,for capillarity when held at a near horizontal level. The pipetsshall fill with sheep plasma or human whole blood within amaximum of 30 s.7.1.1 When using a sealant or plastic closure, the pipetsshould not be filled completely to allow for dry space whichwill be occupied by the sealant or closure. This step should aidin preventing pipet leakage when handled or centrifuged.7.2 Fluidity Test—Test the pipets, both short and long, forfluidity by using sheep plasma (6.3) or human whole blood(6.4).7.3 Sheep Plasma Test:7.3.1 General—Conduct the test initially by preparing re-calcified sheep plasma by the following process:7.3.1.1 Prepare sheep plasma in accordance with the USPassay for sodium heparin.Add 10 mLof prepared sheep plasmato 2.0 mL of the 1.0 % calcium chloride solution used in theheparin assay. Mix the sheep plasma and calcium chloridesolution well.7.3.2 Preparation of Controls—Use samples of both theplain sheep plasma and recalcified sheep plasma as controls inaccordance with the following:7.3.2.1 Positive Control—Fill an uncoated (that is, nonhepa-rinized) pipet with recalcified sheep plasma.7.3.2.2 Negative Control—Fill a coated (that is, heparin-ized) pipet with plain sheep plasma.7.3.3 Procedure—Immediately after the preparation of re-calcified sheep plasma, fill the pipets by immersing the tips inthe recalcified sheep plasma while holding the pipets near thehorizontal level to facilitate quick filling. Rock the pipetseveral times to assure intimate mixing of plasma with heparinon inner surface of capillary tube. Place the pipets in ahorizontal position. At the end of 1 h, inspect the pipetscontaining plasma for evidence of coagulation by carefullyscoring and snapping off segments of tubing and placing themon a flat surface. (Use a black background to facilitateobservation and comparison with control sample.) Coagulationhas occurred if the sheep plasma becomes opaque or if a finefibrin thread is noted.7.4 Human Whole Blood Test:7.4.1 General—Human whole blood may be used instead ofsheep plasma by following the steps outlined as follows:7.4.1.1 Fill the pipets with freshly drawn whole blood byimmersing the tips in the blood while holding the pipets nearthe horizontal level to facilitate quick filling.7.4.1.2 Fill the pipets to within 5 mm from the top (color-coded end) or to approximately 100 mm from the tip on thelonger (Natelson) pipet that may be so marked and place in ahorizontal position.7.4.1.3 At the end of 1 h, expell the blood by means of anaspirator and drain on a clean white tissue.7.4.1.4 Examine the expelled blood with the naked eyeunder normal room lighting (macroscopically) for the presenceof clotting. Coagulation has occurred if a clot of any size isnoted.7.4.2 Controls—The testing laboratory shall use a knowndonor that does not have clotting mechanism deficiencies as acontrol. Use samples of whole blood as controls in accordancewith the following:7.4.2.1 Positive Control—Fill an uncoated (that is, nonhepa-rinized) pipet with human whole blood and run during the testto ensure the suitability of the specimen’s clot formation.Capacity: 310 to 470 µLCoding: Red band-heparin-coated (Type I)Blue band-uncoated (Type II)Dimensions in millimetresA Overall length 73–77B Outside diameter 3.90–4.20C Inside diameter 2.40–2.80D Inside tip diameter 0.70–1.50E Length of taper 6–12F Color band location 0–10FIG. 1 Caraway PipetE787 − 81 (2017)27.4.2.2 Negative Control—Fill a coated tube (heparinized)from a group of known quality with human whole blood andrun during the test to ensure the suitability of the specimen’sclot formation from other than lack of heparin (that is,improper technique or specimen handling).7.5 Resistance to Centrifugal Force Test—Fill the pipets,both long and short, with water, sheep plasma, or human wholeblood; then seal and suspend in a centrifuge. Accelerate thecentrifuge gradually to a speed of 1000 to 1250 RCF.Allow thecentrifuge to run at this speed for 10 min only; then shut off andallow to stop without using the brake.7.6 Heparin Content Test—Determine the heparin content inthe micro blood collection pipets by the method for assayingsodium heparin specified in the latest edition of the UnitedStates Pharmacopeia (USP), or other acceptable methodologythat will correlate and provide equivalent test results. Theresults obtained shall represent the average heparin content onthe inner surfaces of the pipets tested. No heparin from theoutside of the pipet’s surface shall enter the test sample.8. Keywords8.1 blood; disposable; glass; heparin; micro; pipetASTM International takes 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 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 addressed 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 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 service@astm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http://www.copyright.com/Capacity: 220 to 420 µLCoding: Red band-heparin-coated (Type I)Blue band-uncoated (Type II)Dimensions in millimetresA Overall length 145–155B Outside diameter 2.80–3.10C Inside tip diameter 0.75–1.30D Length of taper 6–12E Color band location 0–10 topF Alternative location 100 ± 1 from tipG Inside diameter 1.30–1.80FIG. 2 Natelson PipetE787 − 81 (2017)3