LU100716B1 - Assay components for diagnostic in vitro applications - Google Patents

Abstract

The invention relates to a receptacle and method for in vitro diagnostic applications. The present invention facilitates in vitro diagnostic applications and minimizes the number of potential error sources by providing a receptacle with an immobilized assay component that can be re-suspended.

Description

ASSAY COMPONENTS FOR DIAGNOSTIC IN VITRO APPLICATIONS

DESCRIPTION

Field of the invention [0001] The field of the invention relates to a receptacle and method for in vitro diagnostic applications.

Background of the invention [0002] A variety of in vitro diagnostic assays are routinely carried out in clinical diagnostics and life sciences.

[0003] In many in vitro diagnostic applications, so called beads are added to the reaction in a reaction vessel. These beads are usually in suspension in an aqueous buffer. During transportation, the beads possibly splash onto the vessel wall for example and then dry there. Therefore, the beads must be re-suspended in their transport vessel before they are added to the reaction vessel by pipetting and used for the reaction.

[0004] In standard in vitro diagnostic applications, the reactants can be placed in a previously empty reaction vessel for the detection of analytes. The reactants are mostly in liquid solutions and individually and successively transferred from separate transport vessels into the actual reaction vessel using pipetting needles.

[0005] Some reactants, such as beads for example, do not form a uniform suspension and need to be brought into homogenous suspension inside their transport vessel prior to pipetting. Beads for example tend to sink down inside their solution and collect at the bottom of the vessel, or they splash onto the vessel wall or the lid. The beads need then to be washed down and brought back into suspension by swiveling, agitation, shaking, stirring, pipetting or alternating magnetic fields.

[0006] There are several disadvantages in the prior art. Reactants need to be pipetted separately into the vessel and thereby be distributed homogenously. Homogeneous distribution of beads for instance, is of central importance in quantitative analyzes. Reactants need to be brought into a homogeneous suspension before being pipetted into the reaction vessel in order to avoid measurement errors, because reactants can set down for example. Otherwise, an inhomogeneous bead distribution can lead to an incorrect bead concentration in the reaction vessel and thus to measurement errors.

[0007] In open transport vessels, the concentration of reactants such as beads, may change as a result of evaporation. At a constant pipetting volume, pipetting of the reactants into the reaction vessel then results in an increased concentration of beads in the reaction vessel. This results in measurement errors. Furthermore, the bead concentration in the transport vessel changes as a result of the transfer of liquid, for example washing liquid, from the pipetting needle to the vessel. Pipetting into the reaction vessel with the same pipetting volume thus results in a reduced bead concentration in the reaction vessel and results in measurement errors.

[0008] In the prior art, antibodies or other reactants are bound to a chromatography matrix for example inside a micro flow cell for standard affinity chromatography or bound to a multi well plate for standard enzyme linked immunosorbent assay (ELISA), before being washed round with reactants.

[0009] In standard spotted micro arrays, reactants are spotted or printed onto a carrier matrix, made of glass for example, where they bind or adhere to the surface.

[0010] The United States patent application US 2015/276728 A1 discloses disposable tips comprising mechanically immobilized beads, wherein the beads are lined up in the front part of a plastic tip for washing around with reactants.

[0011] Furthermore, pre-dispensed reagent cartridges are known for single arrays for example to extract DNA or RNA with paramagnetic particles.

Object of the invention [0012] The present invention shall provide a receptacle and a method for facilitated in vitro diagnostic applications minimizing the number of potential error sources.

Summary of the invention [0013] The instant invention provides a receptacle comprising at least one immobilized assay component for an in-vitro diagnostic application. The immobilized assay component may adhere evenly to the receptacle’s inner surface and may comprise bio-reactive particles. The bio-reactive particles might be magnetic beads.

[0014] In a further aspect, the assay component may be attached to the inner surface of the receptacle in a paste-like form, as a gel pastille, as a tablet or as a lyophilized coat application.

[0015] The assay component may comprise at least component selected from the group comprising drugs, chemical or bio-chemical substances, amino-acids, peptides, proteins, nucleic acids, carbohydrates, antibodies, lipids, micelles, vesicles, synthetic molecules, polymers, metal particles, nanoparticles, a solid phase cells, micro-organisms, viruses and magnetic particles.

[0016] Magnetic particles may further comprise at least one functional group selected from the group comprising peptides, nucleic-acids, monoclonal or polyclonal anti-bodies.

[0017] Magnetic particles can be non-covalently bound to a ligand interacting with at least one of a receptor, enzyme, metal compley or chemical or bio-chemical complex.

[0018] In a further aspect of the invention it is intended that the immobilized assay component is soluble in an aqueous solution.

[0019] It is intended that the immobilized assay component is water-soluble and that the immobilized assay component is immobilized with at least one immobilizing component of the group comprising monosaccharides, oligosaccharides, polysaccharides and gelatinizing agents.

[0020] A gelatinizing agent might be selected from the group comprising agarose, agar and gelatin.

[0021] Furthermore, the receptacle may be part of a cartridge comprising at least one further assay component or the receptacle is a tube, a bottle, a multi-well plate, a vial with lid or a cuvette.

[0022] The instant invention further provides a method of carrying out an in-vitro diagnostic assay comprising the steps of immobilizing at least one assay component evenly with at least one immobilizing component selected from the group comprising monosaccharides, oligosaccharides, polysaccharides and gelatinizing agents.

[0023] The assay component may be immobilized by surface drying, lyophilization, gelation, or dissolving in highly viscous medium.

[0024] The immobilizing step may comprise the step of applying the assay component in pasty or lyophilized form to the receptacle.

[0025] The step of bringing the immobilized assay component into the receptacle may comprises the step of inserting the immobilized assay component into the receptacle in form of an effervescent tablet or gel pastille.

[0026] Moreover, the liquid assay component might be a patient sample or a buffer.

Detailed description of the invention [0027] The present invention provides a receptacle and method for facilitated in vitro diagnostic applications with a minimized number of potential error sources.

[0028] According to the present invention, at least one of the reactants, for example the beads, is immobilized in the reaction vessel by applying the reactant in pasty or lyophilized form onto the vessel wall or by inserting the reactant into the receptacle in form of an effervescent tablet or gel pastille. The immobilization of the reactants may be carried out by surface drying, lyophilization, gelation, or dissolving in highly viscous medium.

[0029] The immobilization of the reactants and the ensuring of their correct concentration are integrated into the production process of the reaction vessel.

[0030] The immobilization of reactants in the reaction vessel greatly minimizes the risk of a potential biological hazard by leakage of a liquid during transport. The risk is smallest, when all reactants are immobilized in the reaction vessel. In addition, has the spatial orientation of the reaction vessel during transport and storage no subsequent effects on the functionality and the reaction behavior, if the reactants are immobilized. Furthermore can mistakes due to evaporation not occur, since the immobilized reactants in the reaction vessel are liquid-free.

[0031] The immobilized reactants must be re-suspended before or during the reaction. For resuspension a patient sample or a suitable buffer can be used. Alternatively, another reactant which is either a component of the reaction mixture or is additionally introduced for this step can be used for re-suspending immobilized reactants.

[0032] As a result, the reaction components, preferably the beads, can be distributed more homogeneously and the reliability of the reaction increases. Likewise, the throughput time of the reaction can be markedly reduced by an automated process. Many time-consuming preparation and distribution steps are omitted, so that the process becomes significantly faster. Automation solutions can be simplified and thus be more cost-effective, because the additional mixing of the reactants, as for example the beads, is no longer necessary.

[0033] The reaction vessel may also be part of a complex reaction cartridge which may contain further solid or liquid reactants necessary for the reaction.

[0034] In one embodiment, magnetic beads with a reactive surface for specifically binding and detecting biomolecules are transferred into reaction vessels in aliquots. The goal is that each reaction vessel contains the same amount of corresponding beads and that these beads are immobilized in the vessel in such a way that they can’t be lost through motion during transport and loading of the device. Furthermore, the immobilizing component is at best suitable for stabilizing the beads such that they can be stored and transported at room temperature for a certain time. In addition, the immobilizing component is highly water soluble, which means that the immobilized beads can be re-suspended with the reaction buffer system. Various mono-, oligo- and polysaccharides, as for example trehalose, are conceivable as immobilizing and stabilizing components. These glutinous sugars can be dried or lyophilized. However, it is also possible to use gelling substances such as agarose, agar, gelatin or the like. Important for all immobilizing components, including adhesives and fixatives, is a good solubility in a known aqueous buffer for example over water solubility, pH-dependent solubility or solubility by denaturing salts.

[0035] In the present invention, the beads are immobilized in the reaction vessel before being transported in the finished reaction vessel. The beads are re-suspended before the reaction. As a result, a separate transport vessel and a pipetting step can be saved.

[0036] According to the present invention, in vitro diagnostic applications include assays. An assay is an analytic procedure for qualitatively or quantitatively measuring for instance the presence, amount, and/or functional activity of an analyte. Analytes include, but aren’t limited to, chemical or biochemical molecules, viruses, microorganisms and cells.

[0037] Reactions may be of biochemical or chemical type and include enzymatic, magnetic, luminescent, fluorescent, color change and binding reactions.

[0038] Reaction vessels according to the present invention include manifold receptacles such as micro titer and multi well plates as well as tubes, cuvettes and reaction vials with or without lids. Transport vessels may be chosen from the group comprising but not limited to cartridges, bottles, vials, tubes, cuvettes, well plates, and pipetting tips.

[0039] The pipetting needles may be disposable pipetting tips or can be made of steel for repeated use.

[0040] According to the present invention, assay components include bio-reactive particles. Bio-reactive particles have a specific reactive surface for binding biomolecules and include functionalized beads. Such beads can be functionalized for example with chemical or biochemical molecules, viruses, microorganisms and cells. Biochemical molecules include nucleic acid molecules such as DNA and RNA, as well as amino acid molecules such as peptides and proteins. Moreover, particles and beads can be magnetic. Chemical molecules include metals. Further assay components include patient samples buffers and other reactants.

[0041] Liquid solutions may for example be suspensions or liquids comprising a solved agent.

[0042] The advantages of the invention of the present disclosure can be summarized as follows: - By immobilizing at least one of the reactants in the reaction vessel already, a separate transport vessel and at least one pipetting step are saved. Furthermore, reactants like beads don’t need to be re-suspended before pipetting; - By omitting an additional pipetting step, the potential errors such as all pipetting errors for example related to foam, clots, incorrect pipetting and system-related errors are eliminated; - Detrimental influences from packaging and/or storage fluids can be reduced; - Stirring and mixing of the beads in their storage vessel before adding them to the reaction vessel is omitted. Storage vessels suitable for stirring are therefore no longer required; and - Due to the immobilization of the reactants, such as beads, in the reaction vessel, the spatial orientation of the transport vessel is less important during transportation. The beads can no longer dry on the lid or in a gap, neither can they spill when the vessel is opened. All of the beads can therefore be re-suspended at any time and the yield is thereby ensured.

Claims (16)

A container comprising at least one assay component for in vitro diagnostic use immobilized and adhered to an interior surface of the container. 2. The container according to claim 1, characterized in that the assay component is attached to the inner surface of the container in paste-like form, as a gelatin lozenge, as a tablet or as a lyophilized coating application. 3. The container according to any one of claims 1 or 2, wherein the immobilized assay component is at least one component selected from grappe comprising drugs, chemical or biochemical substances, amino acids, peptides, proteins, nucleic acids, carbohydrates, antibodies, lipids, micelles , Vesicles, synthetic molecules, polymers, metal particles, nanoparticles, solid-phase cells, microorganisms, viruses and magnetic particles. 4. The container of claim 4, wherein the magnetic particles comprise at least one functional grappe selected from the group comprising peptides, nucleic acids, monoclonal or polyclonal antibodies. The container of any one of claims 3 to 6, wherein the magnetic particles are non-covalently bound to a ligand that interacts with at least one of a receptor, an enzyme, a metal complex, or a chemical or biochemical complex. 6. The container of any one of claims 1 to 5, wherein the immobilized assay component is soluble in an aqueous solution. 7. The container of any one of claims 1 to 6, wherein the immobilized assay component is immobilized with at least one immobilizing moiety selected from grappe comprising monosaccharides, oligosaccharides, polysaccharides and gelling agents. 8. The container of claim 7, wherein the gelling agent is selected from the group comprising agarose, agar and gelatin. The container of any one of claims 1 to 8, wherein the container is part of a cartridge comprising at least one further assay component or is a tube, a bottle, a multi-well plate, a vial with a lid or a cuvette. The container of any one of claims 1 to 9, wherein the container is made of a material selected from the group consisting of plastic, glass or metal. 11. A use of a container according to any one of claims 1 to 10 for carrying out an assay. A method for immobilizing an assay component, comprising the step of immobilizing the assay component with at least one stabilizing component selected from the group consisting of monosaccharides, oligosaccharides, polysaccharides and gelling agents. The method of claim 12, wherein the assay component comprises bio-reactive particles. The method of claim 12 or 13, wherein the immobilization step further includes surface drying, lyophilization, gelling or dissolution in high viscosity medium. The method of any one of claims 12 to 14, wherein the immobilizing step further comprises the step of applying the assay component in pasty or lyophilized form to the container wall or bottom. The method of any one of claims 12 to 15, wherein the immobilizing step further comprises the step of introducing the immobilized assay component into the container in the form of an effervescent tablet or gel pastilles.