Microtiter plates are multi-well plates that are adapted for receiving samples to be processed at a plurality of wells. Each well defines a reaction site where a sample is usually mixed with one or more reagents in order to form a sample-reagent mixture which is the subject to analysis e.g. by means of a photometer or a fluorometer.
In recent developments in the field of processing large numbers of samples that have a liquid component or a liquid and a solid component or a liquid and a gel component there is a need for a device that makes possible to separate the liquid from the solid or gel component of each sample rapidly and at low cost. There is in particular a need for a device of this kind which is suitable for processing in the latter way individual samples of very low volume, e.g. lower than 30 microliter.
The invention provides a microtiter plate that is configured and dimensioned for performing the above-mentioned separations for a large number of samples rapidly and at low cost.
The invention also concerns a microtiter plate for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component.
The invention further concerns a system for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component.
The invention further concerns a method for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component.
According to a first aspect of the invention the above aim of the invention is attained with a microtiter plate of the above mentioned kind comprising
According to a second aspect of the invention the above aim of the invention is attained with a system for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component, said system comprising a microtiter plate according to the invention.
According to a third aspect of the invention the above aim of the invention is attained with a method for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component, said method comprising
According to a fourth aspect of the invention the above aim of the invention is attained with a method for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component, said method comprising
The subject invention will now be described in terms of its preferred embodiments with reference to the accompanying drawings. These embodiments are set forth to aid the understanding of the invention, but are not to be construed as limiting.
The invention concerns a microtiter plate for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component, a system for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component, and a method for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component.
According to a first aspect of the invention the above aim of the invention is attained with a microtiter plate of the above mentioned kind comprising
According to a second aspect of the invention the above aim of the invention is attained with a system for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component, said system comprising a microtiter plate according to the invention.
According to a third aspect of the invention the above aim of the invention is attained with a method for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component, said method comprising
According to a fourth aspect of the invention the above aim of the invention is attained with a method for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component, said method comprising
The following examples are provided for illustrative purposes and are not intended to limit the scope of applicants' invention.
A sample of the above mentioned kind is processed in a cavity of the microtiter plate and such processing includes steps which have the effect of extracting biomolecules to be analyzed from the solid or gel component of the sample and transferring those biomolecules to the liquid component of the sample. After this step the liquid component carrying the biomolecules to be analyzed is separated from the solid or gel component of the sample as described in detail hereinafter. This separation is the main aim of the instant invention.
The term “liquid component” comprises any liquid containing biomolecules in solution or any liquid containing a solid component and/or a gel component to form a suspension.
The term “solid component” comprises a solid in the suspension that shall be separated by the proposed structure and method, e.g., chromatography beads.
The term “gel component” comprises one or more pieces of agarose or polyacrylamide gel or another gel. The size of the gel component is limited by the size of the cavity and the size of the connecting structure between the two cavities.
The maximum size of the solid or gel component of the sample is limited by the size of the cavity of the microtiter plate. The minimum size of the solid or gel component that can be separated from the liquid component is limited by the size of the passage which connects said first and second chamber of the cavity with each other.
The term “biomolecule” comprises all organic molecules, including macromolecules, found in living organisms and in particular, proteins, peptides, DNA, RNA and metabolites thereof.
As used herein, the term “having” is equivalent to the term, and shall have the meaning of the term, comprising.
Microtiter plate 11 comprises a single piece body 12. The single piece body 12 is made by injection molding of a suitable plastic material, e.g. Polypropylene (PP), Cyclic Olefin Copolymer (COC), Acrylonitrile/Butadien/Styrene (ABS), Polycarbonate (CC) or Polystyrene (PS), or of other materials known to one of ordinary skill in the art.
Body 12 has an array of cavities 13 and side edges 35, 36. In a preferred embodiment, the grid spacing is of e.g. 4.5 millimeter measured along each of edges 35, 36, i.e. in both X-direction and Y-direction shown by arrows in
As shown in particular by
In a preferred embodiment, single piece body 12 has standard outer dimensions of a microtiter plate and comprises 384 cavities 13. In another preferred embodiment, single piece body 12 has standard outer dimensions of a microtiter plate and comprises 1536 cavities 13. In yet another preferred embodiment, single piece body 12 has standard outer dimensions of a microtiter plate and comprises 96 cavities.
As shown in particular by
As shown by FIGS. 3 to 8, each of cavities 13 has an open upper end 14 and a closed bottom end 15 and each of cavities 13 has a bottom inner surface and comprises a first chamber 16 for receiving a predetermined volume of a sample to be processed, a second chamber 17 and a passage 18 which fluidically connects chambers 16 and 17 with each other. Passage 18 has a top opening 19. The total volume of a cavity 13 is e.g. about 30 microliter. The bottom 23 of chamber 16, the bottom 22 of chamber 17 and the bottom of passage 18 have each an inner surface which is a portion of the inner surface of the bottom 15 of cavity 13.
Chambers 16, 17 and passage 18 have side walls with an inclination angle of about 4 degrees.
In a preferred embodiment, chamber 16 is adapted for receiving a sample having a liquid component or a liquid and a solid component or a liquid and a gel component, whereas chamber 17 is adapted for receiving a pipetting tip 33 shown by
In a preferred embodiment microtiter plate 11 further comprises sealing means 34, shown in
As shown in particular by
A region 21 in the lower part of passage 18 is adjacent to the bottom end 15 of the cavity 13. Region 21 is so configured and dimensioned that it allows passage of liquid from one of chambers to the other only when a centrifugal force is applied to the microtiter plate, but does not allow passage of any solid or gel component the size of which is larger than the width of region 21.
In a preferred embodiment, region 21 of passage 18 is configured and dimensioned as a capillary passage adapted for supporting or facilitating flow of liquid from one of chambers 16, 17 to the other. This is for instance the case when the entire length of region 21 is a capillary adapted for receiving liquid and is thereby able to provide a fluidic connection between the bottom of chamber 16 and the bottom of chamber 17. The bottom of passage 18 (shown in
In another preferred embodiment, region 21 of passage 18 is configured and dimensioned as a capillary passage adapted for preventing a displacement of a solid or gel component of the sample through passage 18.
As shown by FIGS. 3 to 6, in a preferred embodiment the bottom 22 of chamber 17 lies at a lower level than the bottom 23 of first chamber 16 when the microtiter plate 11 is in horizontal position and the upper ends 14 of chambers are on the top side 24 of the microtiter plate 11. As shown by
In a preferred embodiment the inner surface of the bottom 29 of passage 18 which fluidically connects chambers 16 and 17 with each other has a shape that contributes to maximize the centrifugal force exerted on a sample contained in first chamber 16 when microtiter plate 11 is centrifuged by means of a centrifugation apparatus.
In a preferred embodiment of microtiter plate 11 at least a portion of the inner surface of the bottom of each of said cavities 13 is a hydrophilic or hydrophobic surface, or is a surface having a hydrophilic or hydrophobic coating. The purpose of these surface properties is to create flow conditions that are suitable for the intended use of the microtiter plate, e.g. when a preferred sense of flow is suitable for the desired liquid handling process.
In a preferred embodiment at least a portion of or the entire inner surface of the bottom 29 of passage 18 is a hydrophilic surface or is a surface having a hydrophilic coating 25 shown by
In a preferred embodiment at least a portion of or the entire inner surface of the bottom 23 of chamber 16 is a hydrophilic surface or is a surface having a hydrophilic coating (not shown). This feature facilitates the flow of liquid from chamber 16 to passage 18 and thereby ensures that the entire volume of liquid in chamber 16 is transferable to chamber 17 by centrifugation of microtiter plate 11.
In a preferred embodiment at least a portion of or the entire inner surface of the bottom 22 of chamber 17 is a hydrophobic surface or is a surface having a hydrophobic coating (not shown). This feature facilitates the flow of liquid from chamber 16 to passage 18 and thereby ensures that the entire volume of liquid in chamber 16 is transferable to chamber 17 by centrifugation of microtiter plate 11.
As shown by FIGS. 3 to 8, in a preferred embodiment each of cavities 13 tapers towards its bottom end 15, i.e. the cross-section of each cavity 13 diminishes towards the bottom thereof.
As shown by
Solid element 37 is e.g. a filter element having a porous structure that allows passage of particles having a size that is smaller than a predetermined size. Such a filter element is made e.g. of glass or of a plastic material or of other similar materials. In a preferred embodiment, solid element 37 is a membrane that allows passage of particles having a size that is smaller than a predetermined size. Such membrane is made e.g. of a plastic material, paper, a gel or a microfiber or of other materials as known to one of ordinary skill in the art.
In a preferred embodiment solid element 37 is a test element, e.g. a chromatographic test element. Test element 37 is e.g. a membrane or a strip similar to a chromatographic strip which in a first step is able to retain a sample material of a certain kind as a sample flows from chamber 16 to chamber 17 through passage 18 and in a subsequent step is able to release that sample material when said test element is brought in contact with a suitable reagent, the released sample and reagent mixture being then transferable to chamber 17 e.g. by centrifugation of plate 11.
In a preferred embodiment solid test element 37 or at least a portion thereof is a coating having hydrophilic properties or hydrophobic properties. The coating is selected based upon the properties of the sample, such as a biomolecule, to be processed, so that the sample, e.g., one or more biomolecules, preferably bind to the coating and/or otherwise do not pass through solid element 37, e.g., the filter.
In a preferred embodiment, solid element 37 is a filter or test element that at least a portion thereof has a coating having hydrophilic or hydrophobil properties.
According to the invention a first system for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component comprises a microtiter plate 11 of the kind described above with reference to
In a preferred embodiment this first system further comprises a centrifugation apparatus (not shown in the drawings) for centrifugating the microtiter plate 11.
According to the invention a second system for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component comprises a microtiter plate 11 of the kind described above with reference to
In a preferred embodiment this second system further comprises a pipetting tip 33 (shown in
According to the invention a first method for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component comprises
In a preferred embodiment, the above-mentioned transfer of liquid is effected exclusively by means of centrifugal force generated by centrifugation of the microtiter plate 11. The sample volume transferred from chamber 16 to chamber 17 by centrifugation is in the range of about e.g. 0.05 to 2 microliter.
According to the invention a second method for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component comprises
According to the invention a third method for processing samples having a liquid component or a liquid and a solid component or a liquid and a gel component comprises
In a preferred use of the microtiter plate, system and method according to the invention the gel component of the sample contains biomolecules to be analyzed.
Proper use of the microtiter plate according to the invention is subject to the condition that the volume of sample introduced into chamber 16 is smaller than a predetermined maximum value. When this condition is fulfilled only the liquid component of the sample passes through region 21 of passage when transferred from chamber 16 to chamber 17 and any solid or gel component of the sample remains in chamber 16. If the above mentioned condition is not fulfilled, some of the solid and/or gel components of the sample can pass from chamber 16 to chamber 17 through the upper part of passage 18 and the desired separation of the liquid from the solid and/or gel components of the sample is not or not completely achieved. Therefore, in the above described methods the predetermined volume of the sample introduced into chamber 16 is smaller than a predetermined maximum value determined by the shape and the dimensions of the cavity 13, the chambers 16 and 17, and the passage 18.
Although preferred embodiments of the invention have been described using specific terms, such description is for illustrative purposes only, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims.
Number | Date | Country | Kind |
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03079157.8 | Dec 2003 | EP | regional |