US3483986A - Apparatus for performing scientific experiments - Google Patents

Description

A. e. WRIGHT 3,483,986

TIFIC EXPERIMENTS Dec. 16, 1969 APPARATUS FOR PERFORMING SCIEN 6 Sheets-Sheet 1 Filed July 25, 1966 Inventor RI- GoRG MIGHT 37 h *5 Aeam' Dec. 16, 1969 wRlGHT 3,483,986

APPARATUS FOR PERFORMING SCIENTIFIC EXPERIMENTS Filed July 25, 1966 6 Sheets-Sheet 2 A. G. WRIGHT 3,483,986

APPARATUS FOR PERFORMING SCIENTIFIC EXPERIMENTS Dec. 1 6, 1969 6 Sheets-Sheet 5 Filed July 25, 1966 Inventor Wm? M m w A w K G Dv. MB rr L A Dec. 16, 1969 A. G. WRIGHT 3,483,986

APPARATUS FOR PERFORMING SCIENTIFIC EXPERIMENTS Filed July 25, 1966 6 Sheets-Sheet 4 i N 2 I a w I I A X I I I I I I Inventor By @a- @M Dec. 1 6, 1969 A. G. WRIGHT 3,483,986

APPARATUS FOR PERFORMING SCIENTIFIC EXPERIMENTS Filed July 25, 1966 6 Sheets-Sheet 5 1 l 2 U F/ g'9 Inventor By 4 77 wca A. G. WRIGHT Dec. 15, 1969 APPARATUS FOR PERFORMING SCIENTIFIC EXPERIMENTS 6 Sheets-Sheet 6 Filed July 25, 1966 2 1 w. M 5 m 2 0 5 7 F c 0 7 3 6 "m 1 V.

Inventor mm a M w A ,d,

United States Patent 3,483,986 APPARATUS FOR PERFORMING SCIENTIFIC EXPERIMENTS Alfred G. Wright, 7 Cardigan Road, London NW. 6, England Filed .luly 25, 1966, Ser. No. 567,694 Int. Cl. B0141 13/00 US. Cl. 210198 Claims ABSTRACT OF THE DISCLOSURE A tube having an external attachment flange and extending beyond the flange to constitute a spigot of a predetermined length, the outer surface of the spigot being accurately formed as a cylinder which is coaxial with the bore of the tube.

This invention concerns apparatus for performing scientific experiments and is particularly concerned with apparatus for performing experiments exploiting the properties of columnar media, for instance column chroma tography and column (cg. disc) electrophoresis. Al though the invention has especial reference to apparatus particularly designed for convenience in practising such techniques, it should be understood that apparatus in accordance with the invention has utility generally for the performance of experiments in which the properties of a medium in columnar form are to be exploited.

Media that in columnar form have useful properties that may be exploited by various analytical and preparative techniques are, for example, certain adsorbent powders, particulate ionexchange materials both natural and artificial (resins) and certain gels such as for instance starch and polyacrylamide gels. The techniques by which the columnar properties of such media are exploited in general involve supporting the medium in the required columnar condition whilst providing for access to the ends of the column of medium. Hitherto glass has been the most usual material used for so supporting the medium column which has thus been formed in a suitable glass tube. However, glass has some undesirable porperties in connection with certain columnar media and/or techniques to be accomplished therewith and, moreover, does not lend itself to ready connection and disconnection of column end fitting components Providing for access to the ends of the column.

An object of the invention is to provide apparatus that facilitates the performance of experimental techniques such as those discussed above and, in addition, enables the use of glass components to be avoided where the properties of glass are incompatible with columnar media or other reagents and materials that it is desired to utilize in a particular experiment. Thus, more specifically, an object of the invention is to provide columnar apparatus that may be formed in different constructional materials and which avoids or substantially reduces the difficulties inherent in the glass apparatus hitherto available for similar experimental purposes.

In accordance with the present invention there is provided experimental apparatus comprising a column support constituted by a tube having an external attachment flange adjacent to each end thereof, said flange being symmetrical with respect to the bore of the tube, the tube end projecting uniformly beyond such flange to constitute a s igot of predetermined length and having its external surface formed as a cylinder coaxial wit hthe tube bore.

In some embodiments of the invention, the tube of the column support is formed of polyacrylic resin, in which Patented Dec. 16, 1969 'ice case the external attachment flanges are conveniently formed of the same material and may be integral therewith or permanently attached thereto as by solvent welding or the like. However, in preferred embodiments of the invention, the attachment flanges are formed separately of the tube and are detachably mounted thereon, thereby permitting the flanges and tube to be formed of widely differing materials and providing other important advantages as will be explained hereinafter.

Such a column support with a polyacrylic resin tube takes advantage of the desirable chemical and physical properties of polyacrylic resins and, by virtue of the arrangement of the external attachment flanges and end, spigot-constituting, portions of the tube avoids difliculties, due to wall thickness variations and eccentricity generally present in tubes of polyacrylic resins, in connecting such column support to column end fittings in accurate bore-centered leakproof fashion. The ends of the column support constituted by said flanges and spigots are of standardized form permitting simple sealing attachment of column end fittings having complementary flanges, or end surfaces, with recesses to receive the spigot with the trapping of an O-ring between the column support flange and a facing surface on the fitting in question. Similar advantages arise in the case of column supports including glass tubes with detachable attachment flanges.

Both ends of the column support may conveniently be of identical formation for co-operation with mating column end fittings and to facilitate, for instance, inversion of the column between opposite end fittings when such inversion is desired in the practising of a selected technique with the aid of columnar medium within the support.

The invention further provides a range of column end fittings or attachments for use with such column support. Such end fittings or attachments are each characterised by an entry port constituting or surrounded by a recess dimensioned to receive an end spigot of the column support and having, around such port or surrounding recess, an annular surface adapted to engage an Oring placed around the spigot and in engagement with the external attachment flange of the column support, whereby such O-ring may be trapped between such annular surface and the attachment flange to effect a fluid-tight seal.

One such end fitting constitutes a connector piece for coupling two column supports in end-to-end alignment. In one form, such connector piece comprises a disc having a central aperture therethrough corresponding in diameter with the bores of two column supports to be coupled thereby, such aperture being surrounded on each face of the disc with a recess dimensioned to receive an end spigot of a column support, the disc having such a radial extent beyond said recess as to provide the required annular surface for engagement with a sealing O-ring to be trapped between that face and the attachment flange of the column support. In another form, such connector piece comprises a disc having a central aperture therethrough dimensioned to receive the end spigots of a pair of column supports, the disc having a thickness such that when interposed between two column supports having their respective adjacent end spigots located within said aperture, the faces of the disc are spaced by an appropriate distance for providing annular surfaces for engagement with the respective O-rings to be trapped between such disc and the attachment flanges of the column supports.

Another end fitting in accordance with the invention and adapted for coupling to a column support end comprises an oiftake cell in the form of a disc complementary to a column support attachment flange and having on one face a recess dimensioned to receive the end spigot of a column support, the base of said recess having projections to support a column-engaging sinter disc that is thus supported clear of the base of said recess with very low volumetric capacity space between the sinter disc and the recess base, and the base of said recess having a central port communicating through the thickness of the cell disc to provide for connection of a small bore tube to the said space beneath the sinter disc. In one convenient form of such oiftake cell, the said port is formed in a screwthreaded plug screwed into an appropriately screwthreaded aperture in the cell disc, such plug having a taper bore spigot to receive a small bore tube in sealing engagement.

Alternatively, an ofltake cell may comprise a disc complementary to a column support attachment flange, with a central aperture to receive the end spigot of a column support, such aperture being stepped or otherwise formed to receive a moulded plastics (e.g. nylon) plug-in unit of shallow funnel-like form having ribs to support a sinter disc with same volumetric clearance from a base having a central port communicating with a conduit in a spigot.

Another end fitting in accordance with the invention comprises a throughflow cell generally similar in form to the ofltake cell above described, but differing therefrom in having no port in the base of said recess but having, instead, at diametrically opposite locations, inlet and outlet passages that communicate with the recess through the side wall thereof adjacent to the base of the recess. Said inlet and outlet passages terminate at the periphery of the cell disc in bores to receive small bore tubing in fluid-tight connection for passing liquid through the recess beneath a column-engaging sinter disc that is housed therein when such end fitting is attached to a column support.

Other end fittings that may be employed with the column support comprise tubes, elbows, U-connectors and other pipework devices all characterized by having terminations of the form described above for mating engagement with column support ends. All such end fittings may be formed wholly of polyacrylic resin or may be formed or other materials where appropriate or convenient.

Since it may often be desired to connect standard glassware to apparatus including a column support in accordance with the invention, the invention further provides a glassware adaptor fitting for attachment to a column support in accordance with the invention. Such adaptor comprises a polyacrylic tube having an external attachment flange adjacent to one end with a recess to receive an end spigot of a column support with trapping of an O-ring between the adaptor flange and the column support attachment flange, the other end of the adaptor tube having a taper bore ground to constitute a socket receptacle conforming to the standard glass socket receptacle or having its exterior taper ground to conform with the standard glass taper spigot. By means of such adaptor fitting, standard taper ground glassware components may be detachable and interchangeably coupled to the column support.

The column support in accordance with the invention may, if desired, include an external jacket extending between the attachment flanges with appropriately disposed inlet and outlet connections for jacket fluid; the jacket may conveniently be formed of polyacrylic resin united to the attachment flanges of similar material by solvent welding, or the jacket may be of glass or metal suitably sealed to the attachment flanges.

The attachment flanges of the column support are suitably formed for mechanical connection to corresponding flanges of end fittings or attachments to be fitted to the column support; conveniently each such flange has three or more symmetrically disposed peripheral slots to receive coupling bolts that are conveniently formed of polyamide material such as nylon.

Various forms of apparatus embodying the invention are illustrated by way of example in the accompanying drawings in which:

FIGURE 1 is an elevation of a column support assembled with inlet and off-take cells, e.g. for column chromatography;

FIGURE 2 is an exploded perspective view of the assembly of FIGURE 1;

FIGURE 3 is a partial vertical section of the FIGURE 1 assembly with modifications to suit the same for upward flow techniques;

FIGURE 4 is a vertical section of the components at the lower end of an assembly such as shown in FIGURES l, 2, 3;

FIGURE 5 is a fragmentary vertical section of an arrangement for connecting column supports end-to-end;

FIGURE 6 is a diagrammatic part-sectional elevation of a column support and accessories for electrophoresis;

FIGURE 7 is a vertical section on line VII-VII of FIGURE 6;

FIGURE 8 is a transverse section on line VIIIVIII of FIGURE 7;

FIGURE 9 is a vertical section corresponding with FIGURE 7 but showing a modified form of throughflow cell for use with a cold finger equipped column;

FIGURE 10 is a transverse section on line XX of FIGURE 9;

FIGURE 11 is a vertical section corresponding with FIGURE 4 but illustrating a modification of the column support;

FIGURE 12 is an exploded part-sectional elevation of an end of the modified column support illustrated in FIGURE 11; and

FIGURES l3 and 14 are views corresponding with FIGURES 3 and 9 respectively but showing modifications. of the arrangements of those figures especially suitable for large size column apparatus.

Referring first to FIGURES 1 and 2 of the drawings, the assembly there illustrated comprises a column sup port 1 constituted by a tube 2, in this case formed of a polyacrylic resin, having adjacent to each end an attachment flange 3 secured to the tube 2 by, e.g., solvent welding; the tube 2 projects through the flange 3 to define a spigot 4 that projects uniformly beyond the flange for a predetermined length, the end of the spigot being trimmed or otherwise formed to lie in a plane perpendicular to the bore of the spigot and the external surface of the spigot being formed to be truly cylindrical and coaxial with the bore of the spigot. The external face of each flange 3 is formed with an annular recess 5 of predetermined depth around the spigot 4.

In such a column support, the tube 2 may be of any selected length and wall thickness between the flanges 3 and it is immaterial that in this region the tube is neither straight nor has its inner and outer walls truly coaxial; provided that the spigot-constituting portions 4 are of the prescribed dimensions and form, such a column support is fully adapted for connection to other like column supports and accessories as hereinafter described. Thus a column support may be made up from tubing made with wide manufacturing tolerances provided that the wall thickness and external diameter are suflicient to permit the formation of the spigots 4, to the required dimensions, by grinding, machining or other appropriate techniques.

The assembly of FIGURES l and 2 further comprises a pair of ofl'take cells one of which functions as an inlet. Each ofltake cell comprises a disc 6 having a central aperture 7 dimensioned to receive the spigot 4 at the end of a column support, and further to receive a plug-in shallow funnel-like element 8 that seats on a flange 9 in the aperture 7 of the disc 6. The unit 8 has ribs 10 and a central port 11 leading to a conduit 12 in a spigot 13, the arrangement being such that the ribs 10 will support a sinter disc 14 just clear of the base of the unit to provide a chamber of very small volumetric capacity communicating with the port 11 and conduit 12.

As shown in FIGURE 4, the ofltake cell fits on to the spigot 4 at the end of the column support 1 with an O-ring encircling the spigot and trapped between the base of the recess 5 in flange 3 and the face of disc 6 of the ofitake cell. The sinter disc 14 of the lower otftake cell serves to support whatever column material may be disposed within the column support; for downflow techniques it will ordinarily not be necessary to provide a sinter disc at the top of the column and in FIGURE 2 the sinter disc is omitted from the upper ofltake cell since the assembly of FIGURES 1 and 2 is primarily intended for downflow experiments.

As shown, the disc 6 is secured to the column unit by bolts 16 fitted in slots in the disc 6 and flange 3; the flanges 3 and discs 6 may have full circular planforrn but, as shown, it is preferred to form peripheral recesses in these components to facilitate access to components located adjacent thereto.

FIGURE 3 illustrates a modification of the column unit of FIGURES l and 2 to suit this particularly to upward flow experiments with a column material that tends to settle when not traversed by upwardly-flowing fluid.

Thus as shown in FIGURE 3, the upper offtake cell of that unit comprises a unit 17 similar to the unit 8 but differing in that it is dimensioned to fit within the tube 2 and to hold an O-ring 18 sealingly against the bore of the tube 2. The unit 17 is located within the tube 2 by means of a positioning tube 19 that in turn is adjustably supported Within tube 2 by means of an O-ring 2t! trapped between the upper spigot 4 and a tapered recess 21 in a disc 22 secured to the flange 3 by bolts 16. In this case a sinter disc 14a is located in the unit 17 to engage the top of the column material (not shown) within the tube 2. FIGURE 3 also shows a small-bore tube 23 connected to the unit 17 by means of a hollow needle 24.

FIGURE 5 illustrates a convenient arrangement for connecting two column supports 1, 1a, end-to-end, e.g. for supporting an extended column of material with the use of standard, short-length, column units. As shown, the coupling comprises a ring 25 adapted to fit over the butted spigots 4 of the supports 1, 1a and having a thickness appropriate to compress each of the two O-rings 15 between which it is located.

FIGURES 6 to 8 illustrate a column assembly for electrophoretic experiments. This assembly comprises a column support 1 of the form illustrated in FIGURES 1 and 2, having at its lower end a throughfiow cell 26 and its upper end connected to a bufler conduit assembly 27.

The throughfiow cell 26 comprises a disc having a central recess 28 adapted to fit the spigot 4 of the column support 1 with an O-ring 15 in similar manner to the disc 6 of the ofitake cell of FIGURES 1-4. The base of such recess 28 has ribs 29 to support a sinter disc 30 and to define a sinuous small-volume passage between ports 31, 32 at opposite sides of the recess; between the ribs 29 the base of the recess 28 is perforated to expose a semipermeable membrane 33 that is stretched over the lower face of the disc 26 and secured by trapping between annular serrations on the lower face of the disc and an O-ring 34 seated in a recess 35 surrounding a spigot 36 on an adapter ring 37 secured to the lower flange 3 of the column-support 1 by bolts 16. The arrangement is thus such that there is disposed between sinter disc 30 and semipermeable membrane 33 a smallvolume space through which a turbulent flow of washing fluid may pass between ports 31, 32 to sweep electrophoretically mobile materials, escaping from the lower end of the column material, from the underside of the sinter disc 30 for collection.

The conduit assembly 27 comprises a side arm 38 extending from an aperture in an attachment plate 39 that is secured to the upper end of the column support by bolts 16 with interposed O-ring 40, the side arm terminating in a dependent connector for a flexible pipe 41. As shown, the column support is disposed in a buffer tank 42 with electrode 43 and pipe 41 extends into a buffer tank 44 with electrode 45. A connection 46 on the side arm 38 provides for filling the assembly 27 with buffer solution and for introducing materials into the column for electrophoresis. The connection 46 also serves for introduction of a cold finger into the column. When such a cold finger is to be used, the throughfiow cell is preferably modified as shown in FIGURES 9 and 10.

Thus FIGURE 9 illustrates the lower portion of the column support when the arrangement of FIGURES 6 to 8 is modified for use of a cold finger" (water-cooled tube) 50 in the column. In this modified arrangement, the through flow cell 26a differs from the cell 26 in that it has a central boss 51 in its recess 28 and an interrupted concentric rib 52 defining interconnected concentric passages between ports 31a, 32a. As shown the rib 52 is desirably of triangular section so as to have substantially line contact with the underside of the sinter disc 30 to occlude the latter to the smallest possible extent; typically the rib 52 will have a height of about 1 mm. with a base width of about 3 mm.

FIGURES 11 and 12 illustrate a modification of the fundamental column support of the invention. In this arrangement, the tube 2 of the column support 1a is formed with a peripheral groove 55 near each end, such groove receiving a split stepped collar 56 that serves to locate a correspondingly configurated detachable attachment flange 3a. The end portion of the tube 2 beyond the groove 55 is formed to the appropriate dimensions to constitute a spigot 4 equivalent to that of the column support of FIGURES 110. A column support 1a of this modified form is directly interchangeable with that of FIGURES 110, as exemplified by FIGURE 11, which shows an ofitake cell fitted to the column support.

It will be understood that the modified column support 10 permits utilisation therein of tubes 2 of a range of different materials chosen to suit experiments to be performed with the apparatus and, moreover, since the attachment flanges 3a are detachable, the construction of jacketed columns is facilitated.

FIGURES l3 and 14 illustrate modifications that are especially applicable to column supports of large size, for instance column supports in which the tube 2 has an internal diameter of the order of two inches or more.

The arrangement illustrated in FIGURE 13 is a mod ification of the upper end portion of the arrangement of FIGURE 3 and as will be apparent, involves the substitution, for the O-ring 18 of that arrangement, of a pair of O-rings 18a, 18b, that are interposed between a flange on the unit 17 and the end of the positioning tube 19, the O-rings 18a, 18b being adapted to be subjected to axial compression to cause their radial expansion into firm engagement with the bore of tube 2 when the unit 17 has been suitably positioned therewithin, the positioning of the unit 17 being accomplished whilst the O-rings 18a, 18b are uncompressed and, therefore, a free fit in tube 2. For the purpose of applying the required compression forces on the O-rings 18a, 18b, the upper end of the tube 19 has a plug through which rods 1% extend, the rods 19b having their lower ends screwed or otherwise fixed to the unit 17 and having screw-threaded upper ends bearing nuts 190 by means of which the rods 19b may be tensioned between the unit 17 and plug 19a so as to pull the unit 17 upwardly with respect to tube 19. When compressed, the O-rings 18a, 18b grip tube 2 to anchor the unit 17 in its desired position and also form a fluidtight seal around the unit 17.

FIGURE 13 also illustrates a modification of the arrangement for connecting the tube 23 to the unit 17. As shown, the hollow needle 24 of the FIGURE 3 arrangement is replaced, in the FIGURE 13 arrangement, by an externally screw-threaded sleeve 24a that fits over the tube 23 and screws into a threaded bore 12a in the unit 17 to trap a belled-out extremity of tube 23 over a spigot 12b in the bottom of the bore 12a.

The arrangement of FIGURE 14 is a modification of the electrophoresis apparatus of FIGURES 6-8 and is primarily an adaptation of the modification, of that apparatus, shown in FIGURES 9 and 10 to suit the latter to larger sizes of column support. Thus as shown in FIG- URE 14, the adapter ring 37 of the arrangement of FIG- URE 9 is replaced with an adapter ring 37a having a central boss 37b, to support the centre of the semi-permeable membrane 33, and a ring of apertures 37c overlaid by a rotatable shutter 37d having corresponding apertures that may be displaced, relatively to the apertures 370, by rotation of such shutter thereby to adjust the cross-sectional area of the conductive path, in the bufler solution, between the electrode 43 (FIGURE 6) and the membrane 33. It has been found that such adjustment is effective to adjust the current flowing between electrodes 43, 45.

In order to provide for the required turbulent flow of washing fluid in the space between the sinter disc 30 and the semipermeable membrane 33, the throughflow cell 261) shown in FIGURE 14 differs from that of FIG- URES 9 and 10 by having its ribs 52 arranged to define a greater number of divisions of said space into passages for the flow of washing fluid in that space; it will be understood that as the column size increases, so will the number of ribs 52 be increased to maintain the washing fluid passages at a size to produce the required turbulent flow therein.

I claim:

1. In an apparatus for performing experiments to exploit the properties of columnar media such as column cess dimensioned to receive the spigot, said end fitting also including an annular surface for engaging said O-ring whereby the latter is trapped between said annular surface and said attachment flange to elfect a fluid-tight seal, said end fitting constituting a throughflow cell comprising a disc complementary to a column support attachment flange and having on one face a recess dimensioned to receive the spigot of a column support, the base of the recess in said disc having projections to support a columnengaging disc which is to be supported by said projections clear of the base of said recess with very low volumetric capacity space between the column-engaging disc and the recess base, said recess having lateral ports communicating with said space, the base of the recess being perforated, a membrane underlying the perforations in the base of the recess, and an adapter ring secured to said attachment flange and serving to retain said membrane in position against the throughflow cell disc.

2. Apparatus according to claim 1, wherein said tube is formed of polyacrylic resin.

3. Apparatus according to claim 2, wherein the attachment flange is formed integrally with said tube.

4. Apparatus according to claim 1, wherein said attachment flange is detachably fitted to said tube.

5. Apparatus according to claim 4, wherein said tube has a peripheral groove near its end, said groove locating a split stepped collar for locating a complementarily configurated attachment flange.

References Cited UNITED STATES PATENTS 3,010,583 11/1961 Kenyon 210446 X 3,246,920 4/1966 Pall 2l0232 X 3,360,128 12/1967 Federline 210-232 X SAMIH N. ZAHARNA, Primary Examiner US. Cl. X.R.

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