1、BRITISH STANDARD BS1428-D5: 1955 Specification for Syringe pattern micro-pipette Microchemical apparatus GroupD:volumetric apparatusBS1428-D5:1955 This BritishStandard, having been approved by the ScientificGlassware and RelatedLaboratory ApparatusIndustry StandardsCommittee andendorsed by the Chair
2、manofthe ChemicalDivisional Council,waspublished undertheauthorityofthe GeneralCouncilon 29March1955 BSI12-1999 The following BSI references relate to the work on this standard: Committee reference LBC/11 Draft for comment CR(LBC) 6265 ISBN 0 580 34165 8 Co-operating organizations The Scientific Gla
3、ssware and Related Laboratory Apparatus Industry Standards Committee, under whose supervision this BritishStandard was prepared, consists of representatives from the following Government departments and scientific and industrial organizations: Admiralty* Air Ministry Association of British Chemical
4、Manufacturers* Association of Scientific Workers Board of Trade British Association for the Advancement of Science British Chemical Ware Manufacturers Association* British Laboratory Ware Association* British Lampblown Scientific Glassware Manufacturers Association* British Pharmacopoeia Commission
5、British Scientific Instrument Research Association* Chemical Society* Department of the Government Chemist* D.S.I.R. Chemical Research Laboratory* Glass Manufacturers Federation* Institute of Petroleum Ministry of Education Ministry of Health Ministry of Supply* National Physical Laboratory* Oil Com
6、panies Materials Committee Pharmaceutical Society of Great Britain* Royal Institute of Chemistry* Science Masters Association Society of Chemical Industry* Society of Glass Technology* Society for Analytical Chemistry* Standardization of Tar Products Tests Committee The Government departments and sc
7、ientific and industrial organizations marked with an asterisk in the above list, together with the following, were directly represented on the committee entrusted with the preparation of this BritishStandard: Biochemical Society Brewing Industry Research Foundation British Rubber Producers Research
8、Association Glass Delegacy (University of Sheffield) Medical Research Council Physiological Society War Office Individual manufacturers Amendments issued since publication Amd. No. Date CommentsBS1428-D5:1955 BSI 12-1999 i Contents Page Co-operating organizations Inside front cover Foreword ii 1 Sco
9、pe 1 2 Range of sizes 1 3 Material 1 4 Dimensions 1 5 Piston 1 6 Barrel 2 7 Jet 2 8 Dead space 2 9 Definition of capacity 2 10 Tolerance on capacity 2 11 Inscriptions 2 Appendix A Testing of BritishStandard syringe pattern micro-pipette 3 Appendix B Determination of capacity 3 Figure 1 Syringe patte
10、rn micro-pipette 4 Figure 2 Nozzle tip for delivery jet 5 Table 1 Recommended dimensions for syringe pattern micro-pipette 1 Table 2 Calculated dimensions for syringe pattern micro-pipette 2BS1428-D5:1955 ii BSI 12-1999 Foreword This standard makes reference to the following BritishStandard: BS1797,
11、 Tables for use in the calibration of volumetric glassware. This standard is one of a series which is being prepared at the request of the British Laboratory Ware Association. The whole series is to be published as BS1428, “Microchemical apparatus”, and the parts are being issued separately, in the
12、following provisional groups: A. Combustion trains for the determination of elements. B. Apparatus for the determination of elements by other than combustion methods. C. Apparatus for the determination of organic groups. D. Volumetric apparatus. E. General accessory apparatus. F. Filtration accessor
13、ies. G. Heating, cooling and drying accessories. H. Weighing accessories. I. Combustion accessories. J. Electrolytic accessories. K. Accessories for physical gravimetric methods. L. Extraction accessories. This BritishStandard forms Part D5of Group D in the series. Other Parts in Group D have been p
14、ublished as follows: Part D1: Burettes with pressure-filling device and automatic zero; Part D2: Washout pipettes; Part D3: Micro-nitrometer; Part D4: Capillary pipettes; Part D6: Micrometer-operated burette. The apparatus described in this Part is intended for the precise measurement and delivery o
15、f small quantities of liquid such as are required for microchemical work. The pipette operates in the same way as a syringe: no lubricant is used on the piston and the barrel is completely filled with liquid. The volume of liquid expelled from the jet in operation is therefore the volume of that par
16、t of the piston which travels into the barrel when the handle is allowed to fall from the upper to the lower stop. Numerous designs of syringe pipette have been described in technical journals in recent years, most of them adaptations, by the user, of a hypodermic syringe. Various different arrangem
17、ents have been used to form end stops to limit the travel of the piston, all of which entail the use of metal parts attached to the barrel of the syringe. The advantages of the design described in this specification are that the pipette consists solely of two glass components which can be sterilized
18、 when used for bacteriological work, and that there are no adjustments required by the user. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does no
19、t of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, pages1 to5 and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the am
20、endment table on the inside front cover.BS1428-D5:1955 BSI 12-1999 1 1 Scope This BritishStandard specifies a form of pipette suitable for the precise measurement and delivery of a predetermined small quantity of liquid. 2 Range of sizes BritishStandard syringe pattern micro-pipettes shall be of thr
21、ee sizes:0.25,0.5 and1.0ml. Each size may be provided with a long or a short delivery tube (seeFigure 1). 3 Material The barrel and piston shall be made of borosilicate glass, as free as possible from visible defects, and shall be reasonably free from internal strain. 4 Dimensions The only mandatory
22、 dimension for a BritishStandard syringe pattern micro-pipette is the diameter of the ground portion of the piston, which shall be6.0 0.1mm. The remaining dimensions, given in Table 1 and illustrated in Figure 1 andFigure 2, are recommended for the guidance of manufacturers. These dimensions are not
23、 a mandatory part of the specification, but a micro-pipette which, on visual inspection, shows any gross departure from them shall be deemed not to comply with the specification. 5 Piston The piston shall be made from glass rod. The portion which engages in the barrel shall be ground and lapped to a
24、 very fine finish. The departure from circularity of the ground portion, as indicated by the full “throw” of a dial gauge resting on the circumference of the ground portion when it is rotated in a V-block of included angle120 , shall not be greater than0.001mm. The whole of the ground portion shall
25、be straight to0.002mm. At the handle end the rod shall be reduced in diameter and bent at right angles sufficiently sharply to ensure that it rests squarely on the stops, as shown in Figure 1. Table 1 Recommended dimensions for syringe pattern micro-pipette Piston a) Length of ground zone b) Diamete
26、r of handle c) Length of handle projecting beyond stop Barrel d) Length of ground zone e) External diameter of ground portion, not less than f) External diameter of tube from which stops are formed g) Length of capillary tube, including jet. Long pattern Short pattern h) External diameter of capilla
27、ry delivery tube i) Internal diameter of capillary delivery tube j) External diameter of jet at tip k) Wall thickness at tip of jet l) Internal diameter of jet at tip m) Included angle of taper of jet n) Included angle of bevel mm 70 5 15 70 8.0 12.5 75 25 4 1 1.0 to1.5 0.25 to0.5 0.3 to0.5 10 to25
28、45 3BS1428-D5:1955 2 BSI 12-1999 Table 2 Calculated dimensions for syringe pattern micro-pipette 6 Barrel The barrel shall be made from glass tubing which is of uniform circular bore and straight. It shall be lapped or otherwise formed to accept the piston freely without shake. This will ensure that
29、 no liquid leaks from or air enters the barrel when used as described in Appendix B. At the delivery end the barrel shall be smoothly constricted and joined to a capillary tube terminating in a jet. At the other end the barrel shall be joined to a tube of larger diameter which shall be partly cut aw
30、ay to form the upper and lower end stops for the handle of the piston (seeTable 2 for the distance between the stops). All edges shall be ground smooth and the projecting corners chamfered or rounded off. Theplanes of the two ground faces forming the end stops shall be accurately at right angles to
31、the longitudinal axis of the barrel. 7 Jet The capillary delivery tube shall terminate at its lower end in a jet, which shall be made with a gradual taper and bevel as shown in Figure 2, without any sudden constriction at the orifice. Aslight concavity in the taper shall be permitted. The end of the
32、 jet shall be ground smooth and square with the axis and the outer edge slightly bevelled. 8 Dead space The shape of the joint between the barrel and the capillary delivery tube shall be such that the dead space between the piston and the end of the jet does not exceed0.25ml in the closed position.
33、9 Definition of capacity The capacity of a BritishStandard syringe micro-pipette shall be defined as the volume of water at20 C, expressed in millilitres, delivered when the pipette is operated as described in Appendix B. 10 Tolerance on capacity The tolerance on capacity for all sizes of syringe mi
34、cro-pipette shall be 0.002ml. 11 Inscriptions Each pipette shall have permanently and legibly marked on it: a) The nominal capacity, e.g.“0.5ml”. b) The inscription “D.20 C” to indicate that the pipette is calibrated for delivery at20 C. c) An identification number, to be the same on piston and barr
35、el. d) The makers or vendors name or mark. e) The number of this BritishStandard, i.e.“BS1428”. 1) Piston diameter Calculated distance between stops a Nominal capacity of pipette 0.25ml 0.5ml 1.0ml mm 5.9 6.0 6.1 mm 9.14 8.84 8.55 mm 18.29 17.68 17.11 mm 36.58 35.37 34.22 a The dimensions in Table 2
36、 are calculated to give the correct capacity when the piston diameter is within the permitted limits of6.0 0.1mm. No tolerance is given, as the precise distance is controlled by the tolerance on capacity inclause 10 and the measured diameter of the piston. 1) The mark “BS1428” on the product is an i
37、ndication by the manufacturer that it purports to comply with the requirements of this BritishStandard. The BritishStandards Institution is the owner of the registered certification mark shown below: which can be used by manufacturers only under licence from the BSI. The presence of this mark in add
38、ition to the mark “BS1428” on a product is an assurance that the product does comply with the requirements of the standard. It indicates that the BSI has satisfied itself, by inspection and testing, that the system of production, super-vision and control used by the manufacturer is such as to ensure
39、 compliance with all the requirements of the standard. Maintenance of this approved system is secured by periodical inspection and testing on behalf of the BSI. The mark must be accompanied by the name or registered trade mark or licence number of the licensed manufacturer. Further particulars of th
40、e terms of licence may be obtained from the Director, BritishStandards Institution,2Park Street, London, W.1.BS1428-D5:1955 BSI 12-1999 3 Appendix ATesting of BritishStandard syringe pattern micro-pipette The National Physical Laboratory is prepared to accept micro-pipettes for examination for compl
41、iance with the requirements of this BritishStandard. Certificates of values will be issued for satisfactory pipettes if required. Particulars of the fees charged can be obtained on application to the Director, National Physical Laboratory, Teddington, Middlesex. Appendix BDetermination of capacity W
42、hen determining the capacity of a syringe micro-pipette the following procedure shall be observed, the pipette having first been thoroughly cleaned. The pipette is filled with distilled water by withdrawing the piston beyond the upper stop. Thepipette is then inverted to wet the piston and barrel an
43、d the piston pushed in a little to expel any air which was trapped by the first filling.The pipette is then again filled to beyond the upper stop and the outside of the delivery jet wiped free from water with a cloth. The piston is then lowered to the upper stop, the surplus water being expelled int
44、o a glass vessel and the jet touched on to the side of the vessel, to remove any drop which may be adhering to it. The contents of the pipette are then delivered into a weighing vessel by holding the pipette in a vertical position and turning the piston so that the handle clears the upper stop. The
45、piston is allowed to fall under its own weight until it reaches the lower stop. When delivery is complete the jet is touched on the side of the receiving vessel to detach any drop adhering to the jet and the drop is caused to unite with the bulk of the water by tilting the vessel until the surface o
46、f the water touches the drop. The vessel is then reweighed. It is recommended that the receiving vessel should contain water and be counterpoised by a similar vessel of the same internal diameter also containing water. The counterpoise vessel should be tilted momentarily in the same way as the recei
47、ving vessel, so that equal areas of the surface are wetted. It is unnecessary for the vessels to be covered as the evaporation from the two surfaces will be equal. All operations shall be carried out at room temperature. The volume of water delivered by the pipette at20 C shall be calculated by appl
48、ying a correction for water temperature (seeBS1797 2) ). 2) BS1797, “Tables for use in the calibration of volumetric glassware”.BS 1428-D5:1955 4 BSI 12-1999 All dimensions are in millimetres Figure 1 Syringe pattern micro-pipetteBS1428-D5:1955 BSI 12-1999 5 All linear dimensions are in millimetres
49、Figure 2 Nozzle tip for delivery jetBS1428-D5: 1955 BSI 389 Chiswick High Road London W4 4AL BSIBritishStandardsInstitution BSI is the independent national body responsible for preparing BritishStandards. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter. Revisions BritishStandards are updated by amendment or revision. Users of BritishStandards should make sure that they possess the latest amendments or editions. It is the constant aim of BSI to improve the
