WO1991006368A1

WO1991006368A1 - Microtitre plate well inserts

Info

Publication number: WO1991006368A1
Application number: PCT/GB1990/001646
Authority: WO
Inventors: Raymond Edwards; John Alexander Little
Original assignee: Raymond Edwards; John Alexander Little
Priority date: 1989-10-27
Filing date: 1990-10-26
Publication date: 1991-05-16
Also published as: GB8924252D0; GB2239947A

Abstract

The microtitre plate well inserts (2) of the present invention comprises a hollow tubular member with open ends the internal and/or external surface of which is shaped as a zig-zag or pleated wall (6) to provide an extended surface area for a reagent coated on the insert wall surface. Various other embodiments of the well insert are described including an insert formed as a helix and another in the form of a tube of open rectangular mesh.

Description

MICROTITRE PT.AΦW BT.T. INSERTS This invention relates to well inserts for microtitre plates.

Microtitre plates having a plurality of circular wells are extensively used in diagnostic assays. A diagnostic reagent is coated, usually by passive absorption, onto the surface of a microtitre plate and measurement is made using some form of optical signal, such as fluorescence, luminescence or optical density. The known microtitre plate requires mechanical strengh for rigidity, absence of optical interference and a suitable surface for coating of the reagent, however these requirements are often incompatible with each other. An aim of the present invention is to utilize the rigidity and optical qualities of known microtitre plates while improving the surface properties for the coating reagent.

According to the present invention there is provided a well insert for a microtitre plate comprising a hollow tubular member, the internal and/or external surface of which shaped to provide an extended surface area for a reagent coated on the surface, and the surface chemistry of which allows coating or covalent coupling of reagents.

Preferably, the insert is made of a plastics material such as polystyrene or polypropylene.

Embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings, in which:

Figure 1 is a plan view of a microtitre plate fitted with well inserts according to the invention;

Figure 2 is a cross-section taken along the line 2-2 of Figure 1; Figure 3 is a plan view and vertical cross- section of a first embodiment of a well insert;

Figure 4 is a plan view and a vertical cross- section of a second embodiment of a well insert; Figure 5 is a plan view and a vertical cross- section of a third embodiment of a well insert;

Figure 6 is a plan view and a side elevation of a fourth embodiment of a well insert; Figure 7 is a plan view and a side elevation of a fifth embodiment of a well insert;

Figure 8 is a side elevation of a sixth embodiment of a well insert, and

Figure 9 is a side elevation of a seventh embodiment of a well insert.

Figure 1 illustrates a plan view of a microtitre plate 1 made of a plastics material which has mechanical strength and enables the passage of light beams with the absence of optical interference. One such plastics material is polystyrene. However, when a reagent is placed in one of a plurality of wells 2 formed in the plate the reagent is unevenly coated on the internal surface of the well producing edge effects when e.g. an antibody diagnostic test is made. To avoid this problem the present invention provides a hollow tubular insert 3 which is fitted in the well 2 and provides an extended surface area for coating of the reagent. Such an insert may be made of plastics material such as polystyrene or polypropylene which is not constrained by requirements for optical clarity or mechanical strength. The insert may be made from a wide variety of materials some of which are optically opaque. Materials may be suitable for covalent coupling of reagents e.g. cellulose. With reference now to the cross-section shown in Figure 2 the insert 3 is coated with a diagnostic reagent and placed in a well 2 of the microtitre plate 1. The insert is tubular with open ends and does not restrict or interfere with subsequent optical measurements taken by passing a beam of light 4 through the well 2 as used in the assay system.

Figures 3 to 9 illustrate various embodiments of well inserts. Figure 3 illustrates in plan and side elevation an open ended tubular insert 3 extruded from a plastics material with ribs 5 extending vertically around the internal surface. Figure 4 shows similar views to Figure 3 of a second embodiment of a well insert 3 which is extruded from plastics material and is formed with a zig-zag or pleated wall 6.

Figure 5 shows similar view to Figure 3 and 4 of a third embodiment of a tubular well insert 3 the inner wall being formed with raised surface bumps 7 arranged in vertical parallel lines.

Figure 6 shows a fourth embodiment of a well insert in plan and side elevation. The tubular insert 3 has a series of external spaced hoop projections 8 which provide a liquid-tight seal between the insert and well wall.

Figure 7 shows similar views of a fifth embodiment of a well insert 3 with external vertical ribs 9 spaced around the outer periphery of the tubular insert which provide access for the test sample to the space between the insert and the well wall.

Figure 8 is a side elevation of a sixth embodiment of a well insert 3 constructed from a helically formed plastics strip 10.

Figure 9 is a similar view to Figure 8 of a seventh embodiment of a well insert formed as a tubular open rectangular mesh 11.

Embodiments of the well insert are illustrated in which the wall of the insert has an extended surface area which provide a means for enhanced coating of a reagent on its surface, prior to insertion in the well of a microtitre plate for the diagnostic test.

The inserts and microtitre plate may be suitably coloured to distinguish between different reagent batches.

The well inserts can also be used with non- optical detection, such as radioactivity. In this case, the well insert is removed after the assay and measured in a scintillation counter.

Claims

CLAIMS:

1. A well insert for a microtitre plate comprising a hollow tubular member, the internal and/or external surface of which is shaped to provide an extended surface

5 area for a reagent coated on the surface, and the surface chemistry of which allows coating or covalent coupling of reagents.

2. A well insert as claimed in Claim 1 wherein the insert is made from a plastics material.

10 3. A well insert as claimed in Claim 2 wherein the plastics material is polystyrene.

4. A well insert as claimed in Claim 2, wherein the plastics material is polypropylene.

5. A well insert as claimed in Claim 1, wherein the 15 insert is made from cellulose.

6. A well insert as claimed in any of Claims 1 to 5, wherein the insert is formed with a series of internal vertical parallel ribs.

7. A well insert as claimed in any of Claims 1 to 20 5, wherein the insert is formed with a series of spaced external vertical ribs.

8. A well insert as claimed in any of Claims 1 to 5, wherein the insert is formed with a series of internal raised surface bumps.

25 9. A well insert as claimed in any of Claims 1 to 5, wherein the external surface is formed with a series of external spaced hoop projections arranged parallel to one another.

10. A well insert as claimed in any of Claims 1 to 30 5, wherein the hollow tubular member is formed by a helix.

11. A well insert as claimed in any of Claims 1 to 5, wherein the hollow tubular member is formed by an open rectangular mesh.

35 12. A microtitre plate comprising a plurality of wells incorporating one or more of the inserts claimed in any of the preceding Claims 5 to 11.

13. A well insert for a microtitre plate substantially as hereinbefore described with reference to Figures 3 to 9 of the accompanying drawings.