GB2570267A

GB2570267A - Device and method

Info

Publication number: GB2570267A
Application number: GB1710544.6A
Authority: GB
Inventors: gray Jeffrey
Original assignee: Sumitomo Chemical Co Ltd
Current assignee: Sumitomo Chemical Co Ltd
Priority date: 2017-06-30
Filing date: 2017-06-30
Publication date: 2019-07-24
Also published as: GB201710544D0; WO2019002818A1

Abstract

A reader for a biological fluid testing device such as a lateral flow device 110, formed from a first module with a first substrate 102 and either a light source 106, preferably an organic light emitting diode (OLED), or a photodetector 108, preferably an organic photodetector, and a second module with a second substrate 202 with the other of the light source or photodetector. A test region for the testing device 110 is located between the light source and photo detector. The test region is defined by a first alignment structure (protrusions 104 on the first substrate) and a second alignment structure 204 on the second substrate. The second alignment structure forms an alignment layer and has recesses which receive the protrusions. The alignment structures may be formed on the opposing surfaces of the substrates to the light source or photodetector. The reader may also have an opaque mask 112, spacers and apertures. A method of forming the first and second module may include printing, moulding or stenciling the protrusions over the first substrate and the alignment layers over the second substrate respectively. Multiple readers may be manufactured simultaneously as one unit which can be divided into individual readers.

Description

Device and Method

Field of the Invention

The present invention relates to reader devices for biological fluid testing devices, in particular lateral flow strips, and modules and methods for making the same.

Background of the Invention

Lateral flow strips for testing biological liquids are known. In operation, a liquid sample is introduced at one end of a porous strip which is then drawn along the strip by capillary action. If an analyte being tested for is present in the sample, it binds to an indicator material in the test strip and draws the indicator along the strip to a test region.

The test region may be illuminated with a light source and the response of the indicator in the test region maybe detected by a photodetector, for example as disclosed in US 2013/0273528.

It is an object of the invention to provide an accurate reader for a biological fluid testing device.

It is a further objection of the invention to provide an accurate reader for a biological fluid testing device which is simple to manufacture.

It is a yet further objection of the invention to provide an accurate reader for a biological fluid testing device which may be manufactured at low cost.

Summary of the Invention

In a first aspect the invention provides a reader for a biological fluid testing device comprising a first module comprising one of a light source and a photodetector supported on a first substrate; a second module comprising the other of the light source and a photodetector supported on a second substrate wherein the photodetector is configured to receive light emitted by the light source; and a test region between the light source and photodetector for receiving a biological fluid testing device, wherein a first alignment structure is supported by the first substrate, the first alignment structure comprising one or more protrusions; a second alignment structure is supported by the second substrate, the second alignment structure comprising at least one alignment layer having recesses formed therein, wherein the protrusions of the first alignment structure are received in the recesses of the second alignment structure.

Preferably, the biological fluid testing device is a lateral flow strip device.

In a second aspect the invention provides a method of forming a reader for a biological fluid testing device according to the first aspect, the method comprising the steps of receiving the protrusions of the first alignment structure in the recesses of the second alignment structure.

In a third aspect the invention provides a method of forming a first module according to the first aspect, the method comprising the step of printing, moulding or stencilling the protrusions over the first substrate.

In a fourth aspect the invention provides a method of forming a second module according to the first aspect, the method comprising the step of printing, moulding or stencilling the one or more alignment layers over the second substrate.

Description of the Drawings

The invention will now be described in more detail with reference to the figures in which:

Figure 1A is a plan view of a first surface of the substrate of a first module of a lateral flow strip reading device;

Figure 1B is a cross section of the first module;

Figure 2A is a plan view of a first surface of the substrate of a second module of a lateral flow strip reading device;

Figure 2B is a cross section of the second module;

Figure 2C is a plan view of a second surface of the substrate of the second module;

Figure 3 is a cross section of a lateral flow strip reader according to an embodiment of the invention;

Figures 4A and 4B are plan views of first modules with different first alignment structures;

Figure 5 is a cross section of a lateral flow strip reader according to an embodiment of the invention comprising a mask between the light source and the photodetector;

Figure 6 is a cross section of a lateral flow strip reader according to an embodiment of the invention in which the alignment layer forms a mask;

Figure 7 is a cross section of a lateral flow strip reader according to an embodiment of the invention wherein the first alignment structure comprising spacers between the protrusions and the first substrate.

Detailed Description of the Invention

Figure 1A illustrates a first module too of a lateral flow strip reader according to an embodiment of the invention.

The first module comprises a light source 102 supported on a surface of a first substrate. The light source maybe a single light emitting device or a plurality of light-emitting devices. A first alignment structure 104 is formed on an opposing surface of the first substrate. With reference to Figure 1B, the first alignment structure comprises one or more protruding structures protruding from the surface of the first substrate. A proximal end of the protruding structures may be in direct contact with a surface of the substrate, as illustrated in Figure 1, or maybe spaced apart therefrom.The first substrate maybe, without limitation, a glass or plastic substrate. The first substrate may consist of a single layer of substrate material or may comprise two or more layers. Optionally, the substrate comprises a glass or plastic substrate comprising one or more layers selected from filter layers, outcoupling layers and antireflective layers. Preferably, the first substrate consists of a single layer.

Figure 2A illustrates a second module 200 of a lateral flow strip reader according to an embodiment of the invention.

The second module 200 comprises a photodetector 108 supported on a surface of a second substrate 202. The photodetector maybe a single photodetector device or a plurality of photodetector devices. A second alignment structure 204 is formed on an opposing surface of the second substrate. The second alignment structure comprises at least one alignment layer formed on the surface of the second substrate, the at least one alignment layer having one or more recesses formed therein as shown in Figures 2B and 2C. The second substrate may be, without limitation, a glass or plastic substrate. The second substrate may consist of a single layer of substrate material or may comprise two or more layers. Preferably, the second substrate consists of a single layer.

With reference to Figure 2B, the recesses extend through the entire thickness of the at least one alignment layer. In other embodiments at least some, optionally all, of the recesses extend through only a part of the thickness of the alignment layer or layers.

With reference to Figure 3, a lateral flow strip reader is formed by receiving the or each protrusion of the first alignment structure 104 in a corresponding recess of the second alignment structure 204, thereby aligning the first module too comprising the light source 106 and the second module 200 comprising the photodetector 108. The lateral flow strip reader may have a housing (not shown).

Optionally, the protrusions have a height in the range of about 0.1-10 mm, optionally 0.1-5 mm.

In a typical lateral flow test strip 110, a liquid sample is introduced at a first end of the strip and drawn along the lateral flow test strip towards a second end by capillary action. A sample pad maybe provided at the first end of the strip and a collection pad maybe provided at a second end of the strip. The strip may be formed from a fibrous material, for example nitrocellulose. The lateral flow strip may or may not have a housing.

A portion of the lateral flow strip is pre-treated with a labelling material capable of binding to the analyte of interest. The bound analyte may be drawn along the strip to a test region. An immobilising agent maybe present in the test region to immobilise analyte bound to the labelling material. The labelling material may have a distinctive colour and / or may absorb one or more ranges of ultraviolet, visible or infrared light. Labelled particles in the test region may be measured by the lateral flow strip reader. Measurement may be carried out a pre-set time after the liquid sample has been applied to the test strip or dynamic time resolved measurements may be carried out.

Absorbance and / or emission by the labelling material within the test region may be determined in a number of ways, for example by comparing a photodetector signal measured for the test region before and after conducting the assay, by comparing a photodetector signal measurement for the test region with the a photodetector signal measurement for a blank region of the lateral flow strip, or by comparing the response upon illumination of the lateral flow strip with different light-emitting devices of the light source (e.g. devices emitting different wavelengths) illuminating the same or different regions of the strip.

In use, light emitted from the light source 106 passes through the first and second substrates and a test region of a lateral flow strip 110 and is detected by the photodetector 108. The first and second alignment structures together may define a reader test region between the light source 106 and photodetector 108 into which at least the test region of a lateral flow strip, optionally an entire lateral flow strip, may be provided. The first and / or second alignment structures may form a barrier for retaining the lateral flow strip in the reader test region.

Optionally, the test region of a lateral flow strip has an area of up to about too mm x 120 mm, optionally about 10 mm x too mm, and the lateral flow reader may be dimensioned to accommodate at least the test region and, if present, housing of the lateral flow strip.

The lateral flow strip may be aligned within the lateral flow reader such that the test region of the lateral flow strip may be analysed by the reader by any suitable means including, without limitation, one or more of: fixing the lateral flow strip in an aligned position within the lateral flow reader; contacting one or more edges, optionally two or three edges, of the lateral flow strip or housing thereof with the first and / or second alignment structures; providing a registration mark on the lateral flow strip or housing thereof and / or providing a registration mark on the lateral flow strip reader or housing thereof; and providing a housing of the lateral flow strip that engages with a housing of the lateral flow strip reader when the test region is in an aligned position within the reader.

It will be understood that light emitted from the light source passing through the lateral flow strip maybe altered by a material, e.g. the labelling material, such as by absorption and / or downconversion, before reaching the photodetector.

The lateral flow strip reader may be a single use device, for example a device in which the lateral flow strip is not releasable from the lateral flow strip reader, or may be a multiple use device which maybe used with a plurality of different lateral flow strips.The protrusions of the first alignment structure a may have any shape, examples of which are illustrated in Figure 4A and 4B including, without limitation, laterally elongate protrusions and pillar protrusions. The recesses of the second alignment structure have corresponding shapes.

With reference to Figure 5, an opaque mask 112 may be provided between the first and second substrates.

The mask comprises comprises a mask layer supported on the second alignment structure 204. The mask comprises one or more mask apertures in an area of overlap between the emissive area of the light source 106 and the receiving area 108 of the photodetector. The opaque mask may prevent or limit detection of light by the photodetector arising from refraction or reflection of light emitted by the light source before it reaches the photodetector, for example due to scattering of the light passing through the lateral flow strip.

Alignment apertures are formed in the mask which may receive one or more of the protrusions of the first alignment structure. Alignment apertures are preferably outside the overlap area of the light source and the photodetector. The mask may thereby be aligned with the light source 106 and the photodetector 108. A cavity between the mask and the second substrate may be partially or completely filled with a transparent structure (not shown), optionally a transparent film or an optical enhancement structure such as one or more lenses or filters.

In use, the lateral flow strip may be supported on the mask wherein the reader test region is provided between the first substrate carrying the light source and the mask. The mask may have a hydrophobic surface to prevent transfer or absorption of the liquid from the lateral flow strip to the mask.

In other embodiments, the mask may comprise protrusions of a first alignment structure.

The second alignment structure is preferably opaque. Accordingly, the second alignment structure may be formed to serve as a mask as illustrated in Figure 6 which illustrates a lateral flow strip reader according to a further embodiment of the invention which is as described with reference to Figure 5 except that the one or more alignment layers of the second alignment structure 204 extend across an overlap area of the light source and the photodetector. One or more mask apertures are formed in the alignment layer or layers in the overlap area. In use, the lateral flow strip no may be supported by the second alignment structure 204. In this case, the second alignment structure 204 may have a hydrophobic coating to prevent transfer or absorption of the liquid sample from the lateral flow strip to the second alignment structure. The second alignment structure may thus provide the functions of both alignment and masking.

Figure 7 illustrates a lateral flow strip reader according to a further embodiment of the invention which is as described with reference to Figure 5 except that the first alignment structure comprises spacers 114 between the first substrate and the protrusions 116. The spacers may have a dimension that is larger than a corresponding dimension of the recess of the second alignment structure (and, if present, alignment apertures of the mask as illustrated in Figure 7). Thus, protrusions 116 may engage with corresponding recesses and the spacer 114 may maintain a spacing between the first substrate and the second alignment structure. The dimensions of the spacer may be selected according to a required reader test region area or volume. In use, one, two or more edges of a lateral flow strip or a housing thereof may contact a spacer.

Figures 1-7 illustrate devices in which the first alignment structure comprising protrusions is formed on the same substrate as the light source and the second alignment structure comprising recesses is formed on the same substrate and the photodetector. In other embodiments, the first alignment structure comprising protrusions may be formed on the same substrate as the photodetector and the second alignment structure comprising recesses may be formed on the same substrate and the light source. It will be appreciated that the first substrate and / or second substrate is transparent if it is provided between the light source and the photodetector.

It will be understood that a transparent structure as described herein transmits at least some wavelengths of light incident thereon, in particular wavelengths of light emitted by the OLED and / or wavelengths of light following absorption and / or downconversion of light within the lateral flow strip.

Figures 1-7 illustrate lateral flow strip readers in which the light source or photodetector is formed on one surface of a substrate and a first alignment structure or second alignment structure is supported on an opposing surface. In other embodiments, the light source may be formed on the same substrate surface as the first or second alignment structure, and / or the photodetector may be supported on the same substrate surface as the first or second alignment structure. In yet further embodiments, the first alignment structure may be formed on and supported by an edge of the first substrate and / or the second alignment structure may be formed on and supported by an edge of the second substrate.

The first and second alignment structures may each be formed by any suitable method including, without limitation, printing (e.g. 3D printing), moulding or stencilling of the alignment structures. Printing of the alignment structures may include a substrate surface treatment step such as a treatment to modify wetting and / or enhance bonding at the substrate surface The first and / or second alignment structure may be formed by depositing one or more unpatterned layers on the substrate, for example a curable material, followed by patterning by any suitable technique, for example photolithography.

The first and second alignment structures are preferably formed from a polymer or filled polymer including, without limitation, polylactic acid, a photoresist for example SU-8, acrylonitrile butadiene styrene, filled epoxy, and polyethylene terephthlate glycol-modified.

An alignment structure may be formed on a substrate before or after formation a light source or photodetector.

A plurality of photodetectors and first or second alignment structures may be formed on a plate followed by separation, e.g. by scribing, of the plate into a corresponding plurality of individual substrates carrying a photodetector and an alignment structure.

A plurality of light sources and first or second alignment structures maybe formed on a plate followed by division, e.g. by scribing, of the plate into a corresponding plurality of individual lateral flow strip readers, each individual reader comprising a light source, a photodetector and an alignment structure comprising the first and second alignment structures.

A plate carrying a plurality of light sources or photodetectors on one surface, and a plurality of first or second alignment structures on an opposing surface, may be supported on a cutting support providing support along cutting lines to prevent damage to the plate and / or the lateral flow strip reader components supported on the plate.

A first plate carrying a plurality of light sources and one of the first or second alignment structures and a second plate carrying a plurality of photodetectors and the other of the first or second alignment structures may be aligned and then separated, e.g. by scribing, to form a plurality of lateral flow strip readers without the need for aligning individual first and second substrates after scribing. The spacing between first alignment structures and the spacing between second alignment structures on said plates may be selected to allow for alignment of multiple first and second alignment structures at the same time. A cutting spacer may be provided between the first and second substrates to avoid cracking of rigid substrates.

In other embodiments, the first module, the second module and optionally one or more lateral flow test strips may be supplied as a kit which may be assembled to form the lateral flow strip reader.

The light source maybe a single lighting device or a plurality of individual lighting devices. The light source is preferably an organic light-emitting diode (OLED) comprising an anode, a cathode and at least one light-emitting layer between the anode and the cathode. One or more further layers maybe provided between the anode and the cathode, for example charge blocking, charge transporting and charge injecting layers. An OLED light source may be as described in, for example, Organic Light-Emitting Materials and Devices, Editors Zhigang Li and Hong Meng, CRC Press, 2007, the contents of which are incorporated herein by reference.

The photodetector is preferably an organic photodetector comprising an anode, a cathode and an organic electron donor and an organic electron acceptor between the anode and the cathode. In operation a reverse bias may be applied to the photodetector and photocurrent may be measured. Organic photodetectors may be as described in, for example, Ruth Shinar & Joseph Shinar “Organic Electronics in Sensors and Biotechnology” McGraw-Hill 2009, the contents of which are incorporated herein by reference.

The invention has been described herein with reference to a reader for a lateral flow strip device, however it will be appreciated that a reader as described herein may be used for reading other biological fluid testing devices including, without limitation, a microfluidic device and the device maybe dimensioned to accommodate at least a test region of a microfluidic device as described herein. A microfluidic device may contain recesses on one or more surfaces thereof to align with corresponding microfluidic device alignment protrusions supported on the first or second substrate.

Although the present invention has been described in terms of specific exemplary embodiments, it will be appreciated that various modifications, alterations and/or combinations of features disclosed herein will be apparent to those skilled in the art without departing from the scope of the invention as set forth in the following claims.

Claims

1. A reader for a biological fluid testing device comprising a first module comprising one of a light source and a photodetector supported on a first substrate; a second module comprising the other of the light source and a photodetector supported on a second substrate wherein the photodetector is configured to receive light emitted by the light source; and a reader test region between the light source and photodetector for receiving a biological fluid testing device, wherein a first alignment structure is supported by the first substrate, the first alignment structure comprising one or more protrusions; a second alignment structure is supported by the second substrate, the second alignment structure comprising at least one alignment layer having recesses formed therein, wherein the protrusions of the first alignment structure are received in the recesses of the second alignment structure.

2. A reader for a biological fluid testing device according to claim 1 wherein the biological fluid testing device is a lateral flow strip device.

3. A reader for a biological fluid testing device according to claim 1 or 2 further comprising an opaque mask between the light source and the photodetector, the opaque mask comprising one or more apertures for receiving one or more of the protrusions of the first alignment structure.

4. A reader for a biological fluid testing device according to claim 3 wherein the opaque mask is supported on the second alignment structure.

5. A reader for a biological fluid testing device according to claim 1 or 2 wherein the alignment layer extends over an overlap area between the light source and photodetector and wherein the alignment layer comprises mask apertures in the overlap area.

6. A reader for a biological fluid testing device according to any one of the preceding claims wherein the first alignment structure comprises spacers between the first substrate and the protrusions.

7. A reader for a biological fluid testing device according to any one of the preceding claims wherein the light source is supported on the first substrate and the photodetector is supported on the second substrate.

8. A reader for a biological fluid testing device according to any one of the preceding claims wherein the photodetector or the light source and the first alignment structure are formed on opposing surfaces of the first substrate.

9. A reader for a biological fluid testing device according to any one of the preceding claims wherein the photodetector or the light source and the second alignment structure are formed on opposing surfaces of the second substrate.

10. A reader for a biological fluid testing device according to any one of the preceding claims wherein the light source is an organic light-emitting device.

11. A reader for a biological fluid testing device according to any one of the preceding claims wherein the photodector is an organic photodetector.

12. A reader for a biological fluid testing device according to any one of the preceding claims wherein the light source is a single light-emitting device.

13. A reader for a biological fluid testing device according to any one of claims 1 to 11 wherein the light source comprises a plurality of light-emitting devices.

14. A reader for a biological fluid testing device according to any one of the preceding claims wherein the photodetector is a single photodetector device.

15. A reader for a biological fluid testing device according to any one of claims 1 to 13 wherein the photodetector comprises a plurality of photodetector devices.

16. A method of forming a reader for a biological fluid testing device according to any one of the preceding claims, the method comprising the step of receiving the protrusions of the first alignment structure in the recesses of the second alignment structure.

17. A method of forming a first module according to any one of claims 1-15, the method comprising the step of printing, moulding or stencilling the protrusions over the first substrate.

18. A method of forming a second module according to any one of claims 1-15, the method comprising the step of printing, moulding or stencilling the one or more alignment layers over the second substrate.

19- A method according to any of claims 16-18, the method comprising the steps of providing a first plate comprising a plurality of one of the photodetector and light source and a corresponding plurality of first alignment structures; providing a second plate comprising a plurality of the other of the photodetector and light source and a corresponding plurality of second alignment structures supported thereon; and receiving the protrusions of the plurality of first alignment structures in the recesses of the plurality of second alignment structures.

20. A method according to claim 19 comprising the step of dividing the plate into individual biological fluid testing device readers.

Intellectual Property Office

Application No: GB1710544.6 Examiner: Ms Annabelle

Whatmough

Claims searched: 1-20 Date of search: 13 December 2017

Patents Act 1977: Search Report under Section 17

Documents considered to be relevant:

Category Relevant to claims Identity of document and passage or figure of particular relevance X 1-20 GB2541424 A (MOLECULAR VISION LTD) See figures 4 and 5 and paragraphs 13 and 81-83 X 1-4 and 10-18 US2016/121323 Al (GRACE BIO LABS INC) See figure 4 and paragraphs 54-68 A - US2016/310948 Al See the EPODOC abstract and figures 2b and 2c. A - US2006/008896 Al (CHURCH & DWIGHT CO INC) See figure 8 and paragraph 52 A - EP1222462 A2 (IMP COLLEGE INNOVATIONS LTD) See figure 2, paragraph 21 and 65. A US2009/306543 Al (BAMBURGH MARRSH LLC) See paragraph 71 and figure la.