WO2010080287A1

WO2010080287A1 - Method and apparatus for treating slides with fluids

Info

Publication number: WO2010080287A1
Application number: PCT/US2009/067042
Authority: WO
Inventors: Brian H. Kram; Vincent R. Rizzo
Original assignee: Ventana Medical Systems, Inc.
Priority date: 2008-12-19
Filing date: 2009-12-07
Publication date: 2010-07-15

Abstract

An apparatus and method includes treating a microscope slide with fluids. A slide conveying device can be configured to receive and carry a slide in a substantially vertical orientation. The slide receives a dispensed fluid on a first surface of the slide and the slide can be moved up and down with the fluid forming a liquid bearing surface between the slide and a treatment station base.

Description

METHOD AND APPARATUS FOR TREATING SLIDES WITH FLUIDS

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of U.S. Provisional Patent Application No. 61/139,489 filed on December 19, 2008, which is incorporated herein in its entirety.

FIELD

[001] This application concerns embodiments of a method and apparatus for the fluid treatment of a material on various surfaces and, more particularly, the fluid treatment of biological tissue samples fixed on microscope slides.

BACKGROUND

[002] The analysis of biological tissue samples is a valuable diagnostic tool used by pathologists to diagnose illnesses and medical researchers to obtain a variety of useful information. Such analysis can include, for example, immunostaining, which involves using antibodies to detect specific proteins in biological tissue samples.

[003] Immunostaining typically involves a number of tightly sequenced steps and requires the use of expensive reagents. For example, immunostaining procedures can include pre- treating a tissue section to reduce non-specific binding, antibody treatment and incubation, enzyme-labeled secondary antibody treatment and incubation, substrate reaction with the enzyme, counterstaining, and the like. In addition, between each treatment step, one or more rinsing steps can be performed to remove unreacted residual reagents from the prior step. U.S. Patent Publication 2005/0164374, the entire disclosure of which is hereby incorporated by reference, describes many of these various steps.

SUMMARY

[004] The embodiments described herein provide a number of significant advantages over traditional methods for applying fluidic treatments to material samples mounted on flat surfaces, such as microscope slides. Among the other advantages described herein, the following embodiments advantageously reduce the amount of fluid required to treat each sample and provide a compact and efficient means for achieving fluid treatment of materials disposed on one or more microscope slides.

[005] In one embodiment, an apparatus for treating a microscope slide with a thin film of fluid is provided. The apparatus comprises a station base that has a side surface, a slide conveying device, and a fluid dispensing device. The slide conveying device is configured to receive a microscope slide having a material sample disposed on a first surface of the microscope slide. The slide conveying device is further configured to move the microscope slide from a first position to a second position, with the microscope slide being in a substantially vertical orientation when the microscope slide is in the second position. The fluid dispensing device is configured to dispense a volume of fluid while the microscope slide is in the first position. At least a portion of the dispensed fluid contacts one or more of the first surface of the microscope slide and the side surface of the station base and is captured in a gap between the first surface of the microscope slide and the side surface of the station base. Movement of the microscope slide from the first position to the second position causes the dispensed fluid to fill an expanding gap between the first surface of the microscope slide and the side surface of the station base. The fluid received and held in the gap forms a liquid bearing surface that prevents the material sample from contacting the side surface of the station base.

[006] In specific implementations, the volume of fluid dispensed by the fluid dispensing device is between about 0 and 100 microliters, and, more specifically, between about 0 and 30 microliters and between about 30 and 100 microliters. In other specific implementations, the slide conveying device is configured so that a lower portion of the microscope slide contacts the side surface of the station base when the microscope slide is in the first position. In other specific implementations, the station base further comprises a top surface, and the area of the side surface that is near the top surface is rounded or beveled, the rounded or beveled portion being a part of the side surface where a dispensed fluid can be captured when the microscope slide is in a first position . In other specific implementations, the side surface is substantially vertical. In other specific implementations, the station base is configured in the shape of a horizontally oriented cylinder, with the side surface of the station base being rounded. [007] In other specific implementations, the slide conveying device is configured to reciprocate the microscope slide up and down between at least a portion of area between the first and second positions. In still other specific implementations, the slide conveying device is configured to substantially or completely disengage the microscope slide from the side surface of the station base. The disengagement of the microscope slide from the station base causes the fluid held in the gap between the microscope slide and the side surface to be released and flow downward along the side surface of the station base. In other specific implementations, the station base comprises a membrane covering on its side surface. In yet other specific embodiments, the station base can include a heating and/or cooling device, such as a resistive heater coupled with or integral to the station base, a radiant heater configured to heat one or more surfaces (such as the side surface) of the base station or a Peltier device coupled with or integral to the station base. In still further embodiments, one or more station bases can be enclosed in one or more covered or sealed chambers, within which one or more chambers the environment (such as humidity levels, temperature and/or pressure) can be independently or simultaneously controlled.

[008] In other specific implementations, the slide conveying mechanism is configured to receive and move a plurality of slides. In addition, the side surface of the station base can be configured to treat a plurality of slides at one time.

[009] In another embodiment, an automated apparatus for treating a plurality of slides with a thin film of fluid is provided. The apparatus comprises a treatment station, a slide conveying device, and a fluid dispensing device. The treatment station comprises a station base that has a side surface. The slide conveying device is configured to receive a plurality of microscope slides. Each microscope slide has a material sample disposed on a first surface of each respective microscope slide. The slide conveying device is configured to carry the plurality of microscope slides and move the microscope slides to and from the treatment station. The slide conveying device is also configured to move the plurality of slides up and down between a first position and a second position. A fluid dispensing device is provided at the treatment station. When one of the plurality of slides is positioned at the treatment station, the fluid dispensing device dispenses a volume of fluid that is about 30 microliters or less. The fluid is dispensed such that at least a portion of the dispensed fluid contacts one or more of the first surface of the microscope slide and the side surface of the station base. The movement of each respective microscope slide from the first position to the second position by the slide conveying device causes the dispensed fluid to be received and held in a gap between the first surface of the microscope slide and the side surface of the station base. The fluid received and held in the gap forms a liquid bearing surface that prevents the material sample from contacting the side surface of the station base.

[010] In specific implementations, the slide conveying device is configured to independently move each of the plurality of microscope slides to and from one or more treatment stations and up and down between the first and second positions. In other specific implementations, the apparatus further comprises a separate incubation housing and the slide conveying mechanism is configured to move the microscope slides from the treatment station to the incubation housing.

[Oi l] In another embodiment, a method of treating a microscope slide with a thin film of fluid is provided. The method comprises providing a microscope slide with a material sample disposed on a first surface of the microscope slide, providing a station base having a side surface, and providing a fluid dispensing device. The microscope slide is positioned with the first surface of the microscope slide facing the side surface of the station base. A volume of fluid is dispensed from the fluid dispensing device so that at least a portion of the dispensed fluid contacts one or more of the first surface of the microscope slide and the side surface of the station base. The microscope slide is moved downward in a substantially vertical orientation along the side surface of the station base. The movement of the microscope slide downward causes at least a portion of the dispensed fluid to contact the material sample and form a liquid bearing surface between the material sample and the side surface of the station base. The liquid bearing surface prevents the material sample from contacting the side surface of the station base while the microscope slide moves along the side surface of the station base.

[012] In specific implementations, the act of dispensing fluid comprises dispensing about 30 microliters or less of fluid. In other specific implementations, the act of positioning the microscope slide with the first surface facing the side surface comprises moving the microscope slide so that a lower portion of the microscope contacts the side surface of the station base. In other specific implementations, the method further comprises reciprocating the microscope slide up and down while maintaining the liquid bearing surface of fluid between the first surface of the microscope slide and the side surface of the station base. In other specific implementations, the method further comprises disengaging the microscope slide from the side surface of the station base. The disengagement of the microscope slide from the station base causes the fluid that was held in the gap to be released. The liquid flows downward along the side surface of the station base.

[013] In other specific implementations, an incubation housing is provided for incubating a microscope slide that has received a fluid treatment. The microscope slide is conveyed to the incubation housing for incubation.

[014] The foregoing and other objects, features, and advantages of the invention will become more apparent from the following detailed description, which proceeds with reference to the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

[015] FIG. 1 shows a side view of one disclosed embodiment for applying a fluid treatment to a material sample on a microscope slide.

[016] FIG. 2A shows a microscope slide in a disengaged position relative to a fluid treatment station base before undergoing a fluid treatment.

[017] FIG. 2B shows a microscope slide in a second position relative to a fluid treatment station base, with a lower portion of the microscope slide engaged with the fluid treatment station base to receive a fluid treatment.

[018] FIG. 2C shows a microscope slide in a third position relative to a fluid treatment station base, with a larger portion of the microscope slide engaged with the fluid treatment station base than that shown in FIG. 2B.

[019] FIG. 2D shows a microscope slide in the same position as shown in FIG. 2B, which the microscope slide can be returned to after having been in the third position shown in FIG. 2C. [020] FIG. 2E shows a microscope slide disengaged from the fluid treatment station base after undergoing a fluid treatment.

[021] FIG. 3 shows a side view of another embodiment for applying a fluid treatment to a microscope slide.

[022] FIG. 4 shows a top perspective view of one embodiment of a disclosed apparatus for treating microscope slides with fluids, including a conveying device for moving microscope slides from one position to another.

[023] FIG. 5 shows a partial side perspective view of one embodiment of a disclosed apparatus for treating microscope slides with fluids, with a mechanism for raising or lowering the microscope slides.

[024] FIG. 6 shows another partial side perspective view of one embodiment of a disclosed apparatus for treating microscope slides with fluids, with a mechanism for raising or lowering the microscope slides.

[025] FIG. 7 shows a schematic view of one embodiment of a disclosed apparatus for treating microscope slides with fluids, with the apparatus including various fluid treatment stations.

[026] FIG. 8 shows a side view of one embodiment of a disclosed embodiment in which a plurality of microscope slides can be treated with fluids at one treatment station.

DETAILED DESCRIPTION

[027] As used in this application and in the claims, the singular forms "a," "an," and "the" include the plural forms unless the context clearly dictates otherwise. Additionally, the term "includes" means "comprises." Further, the term "coupled" generally means electrically, electromagnetically, and/or physically (e.g., mechanically or chemically) coupled or linked and does not exclude the presence of intermediate elements between the coupled items.

[028] As used herein, "automated" refers to one or more steps that are executed by substantially mechanical, electro-mechanical, computer, and/or electronically. It does not exclude some human intervention steps such as loading samples on slides and/or manually performing one or more of the features or steps described herein.

[029] Although the operations of exemplary embodiments of the disclosed method may be described in a particular, sequential order for convenient presentation, it should be understood that disclosed embodiments can encompass an order of operations other than the particular, sequential order disclosed. For example, operations described sequentially may in some cases be rearranged or performed concurrently. Further, descriptions and disclosures provided in association with one particular embodiment are not limited to that embodiment, and may be applied to any embodiment disclosed.

[030] Moreover, for the sake of simplicity, the attached figures may not show the various ways (readily discernable, based on this disclosure, by one of ordinary skill in the art) in which the disclosed system, method, and apparatus can be used in combination with other systems, methods, and apparatuses.

[031] Referring to FIG. 1, a microscope slide 10 is shown engaged with a fluid treatment station. In particular, slide 10 is positioned to abut a membrane 12 that is attached to (or otherwise positioned on) a surface of a fluid treatment station base 14. As used herein, the term "abut" means positioning one element in close proximity to another element, with or without contact. As used herein "microscope slide" and "slide" refer to any flat surface of any size, shape, and material that is capable of conveying a tissue or other material sample in the manner described herein. For example, slide 10 can comprise a traditional glass slide that is 1 inch by 3 inch by 1 mm, such as those readily available through the Erie Scientific Company.

[032] The membranes described herein can comprise any of a variety of materials. For example, U.S. Patent Publication 2005/0164374 describes materials that can be used in connection with the embodiments described herein, including a membrane that comprises a gas permeable material on one surface (the surface facing the slide) and a liquid-impermeable backing on the other surface (the surface adjacent the station base). In addition, in any of the embodiments described herein, the membrane can be omitted and the station base itself can be used as the contacting surface. If the station base is to be used alone, the station base can be formed from any suitable material, such as metals or metal alloys and/or suitable polymeric materials, including aluminum, stainless steel, or other similar materials. Moreover, such station bases can be formed with various coatings, such as a Teflon coating, and/or with any of the materials described herein and in U.S. Patent Publication 2005/0164374.

[033] A thin slice or section of sample material 16 can be disposed on a first surface 18 of the slide 10. The material 16 can be, for example, a tissue sample which has been appropriately prepared for receiving the fluid treatments described herein. "Sample material" or "material sample" refer to any material that can be disposed and treated on a slide for analysis, including any tissue or biological sample obtained from, derived from, or containing any organism including a plant, an animal, a microbe, or even a virus. Particular examples of such sample materials can include a collection of cells, such as sections of organs, tumors sections, bodily fluids, smears, frozen sections, cytology preps, and cell lines. As described in U.S. Publication No. 2005/0164374 (incorporated herein by reference), before being disposed on the slide, the sample material can be frozen or fixed, dehydrated, treated with a wax or other plastic substance, further sliced, and/or exposed to other solvents or treatments. The type and size of the sample material, along with its prior treatment, can vary depending on the particular analysis being performed.

[034] As shown in FIG. 1, the slide 10 is desirably oriented vertically, or substantially vertically. As the slide 10 moves into position for receiving a fluid treatment, a lower portion 22 of the first surface 18 is brought adjacent to the membrane 12 of the base 14. If desired, the slide 10 can be brought into contact with the membrane 12. Alternatively, slide 10 can be brought close enough to membrane 12 so that a dispensed fluid (described below) can be captured between the slide and membrane surfaces.

[035] A volume of fluid 20 is desirably dispensed from a fluid dispensing device 24 (e.g., a nozzle). Fluid dispensing device 24 is desirably connected to a reservoir 26 that contains one or more reagents or other fluids, with the fluid dispensing device 24 being positioned and/or oriented so that at least a portion of the dispensed volume of fluid 20 enters a wetting region 25. The "wetting region" is defined herein as the region at or adjacent to the area where the slide 10 contacts or abuts the base 14 (or membrane 12). FIG. 1 shows one example of a wetting region; however, it should be understood that the wetting region in a particular application can be different than that show in FIG. 1. For example, the wetting region could be larger or smaller, and/or could comprise an area above or below the area where the slide contacts or abuts the base.

[036] Referring again to FIG. 1 , fluid 20 can be dispensed onto the slide 10 at a position above the wetting region and the fluid can flow downward into the wetting region. In addition to dispensing the fluid in droplets shown in FIG. 1, the volume of fluid 20 can be "painted," "misted," ink-jetted, and/or dispensed onto the wetting region or onto the slide surface in any manner effective to achieve the desired result(s), including wetting the sample.

[037] The dispensing of reagents and other fluids is desirably automated. Thus, the selection of the fluid to be dispensed and the amount and manner in which the fluid is dispensed can be computer controlled. U.S. Patent Publication 2008/0102006, the entire disclosure of which is incorporated herein by reference, describes robotic fluid dispensers that are operated and controlled by microprocessors.

[038] The membrane 12 and base 14 are desirably formed with a substantially rounded or beveled surface 32 (which is part of side surface 28) so that the radius of the membrane 12 and base 14 provide a lateral tolerance for receiving dispensed fluids. Although a substantially rounded or beveled surface is preferable, the side surface 28 (at an area near the top surface 30) can alternatively comprise any shape surface that functions to direct fluid 20 from the upper part of the side surface into a gap between the slide 10 and side surface 28. For example, if the angle between the top surface 30 and side surface 28 of the membrane 12 was 90 degrees (with the top surface 30 being oriented horizontally), fluid received onto the top surface 30 would not roll towards the wetting region. However, if fluid 20 is dispensed onto rounded surface 32, fluid 20 flows downward toward the wetting region and into the gap between the slide 10 and the side surface 28 of the membrane 12. Alternatively, or in addition to the rounded surface 32, if desired, the top surface 30 can be oriented at a non- orthogonal angle relative to the slide and at an angle effective to facilitate fluid flow to the gap. [039] Slide 10 can also be initially positioned so that the slide 10 is not oriented substantially vertical. For example, an upper portion of the slide 10 (e.g., using the slide clip 38) can be moved so that the slide forms an angle less than 90 degrees relative to the top surface 30 of the membrane 12. "Tilting" the slide 10 in this manner can ensure that the first surface 18 will contact the side surface 28 of membrane 12 when the slide is positioned to receive a volume of fluid from the fluid dispensing device 24. To avoid direct contact of material 16 with the membrane 12, however, slide 10 is desirably positioned to contact the side surface 28 at the lower portion 22 or at an upper portion of the slide 10 (e.g., an area below or above the location of the material 16).

[040] After the desired volume of fluid 20 is dispensed from the fluid dispensing device 24, fluid 20 flows downward (in the direction of arrow 34) and contacts the wetting region. Once fluid has been received in the wetting region, the slide 10 can be moved downward (in the direction of arrow 36) along the side surface 28 of membrane 12.

[041] FIGS. 2 A - 2E illustrate schematically the dynamics of the fluid 20 as the slide 10 is moved substantially vertically (e.g., up and down) along the side of the membrane 12. As shown in FIG. 2A, a slide 10 with a material 16 (e.g., a tissue sample) disposed on a first surface 18 can be first positioned above membrane 12 (or above station base 14 if no membrane is provided).

[042] As shown in FIG. 2B, the slide 10 can be moved to another position where a lower portion 22 of the slide 10 contacts the side surface 28 of membrane 12. Slide 10 desirably has a slide clip 38, which facilitates its movement upwards and downwards. The configuration of the slide clip 38 can vary and any structure can be used so long as that structure is capable of grasping or holding the slide 10 and providing a mechanism for attaching the slide 10 to a conveying device (as described in more detail below). For example, slide clip 38 can comprise a simple clamp with a loop or hooking mechanism above the clamp for removably coupling the microscope slide to the conveying device.

[043] Thus, a volume of fluid 20 can be dispensed into the wetting region where the slide 10 contacts or abuts the base 14 (or membrane 12) and the slide 10 can be moved downward so that the material 16 contacts the fluid 20. FIG. 2B illustrates fluid 20 entering into a gap between the slide 10 and the side surface 28. The gap can be a variable gap, in that it can expand and/or contract in size. Desirably, the gap is expandable. For example, the gap can increases as fluid 20 is received into the gap. For example, if the slide 10 is initially in contact with the side surface 28, the gap may comprise only the distance between adjacent particles of the slide 10 and side surface 28. Thus, even if two surfaces physically contact one another, they will form a gap therebetween, albeit very small. However, as fluid 20 is dispensed into the wetting region fluid 20 enters the gap (either by flowing directly into the gap or by being forced into the gap as slide 10 moves downward) and the gap expands to accommodate the volume of fluid received into the gap. By configuring the gap to expand in this manner, fluid 20 can be easily dispensed and received in the gap without significant concern for the exact position of the slide 10 relative to the side surface 28.

[044] The gap can also be configured to contract by applying a lateral force to the slide, which can cause at least some of the fluid 20 received in the gap to be expelled from the gap and/or spread more thinly across the slide surface.

[045] For illustrative purposes, FIG. 2C schematically illustrates fluid 20 as covering only a central portion of the slide and not extending from one side of slide 10 to the other or to the bottom of the slide 10. It should be understood, however, that (as long as a sufficient volume of fluid is dispensed) the fluid would typically spread to fill the entire space (gap) between the slide 10 and the side surface 28. In addition, the volume of fluid 20 is a determining factor of the size (width) of the gap between the side surface 28 and the slide 10.

[046] In the embodiments of the apparatus and method for use as described herein, the volume of fluid 20 dispensed for each fluid treatment of a single, traditional-sized slide is desirably about 30 microliters or less. A person of ordinary skill in the art will appreciate that this fluid volume can vary, such as from greater than 0 to at least about 100 microliters. Because of micro-fluid dynamics, as the volume of fluid 20 enters the gap between the first surface 18 of slide 10 and the side surface 28 of membrane 12, slide 10 will no longer be in direct contact with the side surface 28 and instead will "float" on fluid 20 as it wicks between the two surfaces. As the slide 10 floats, the space between the first surface 18 of slide 10 and the side surface 28 of membrane 12 accommodates the volume (~ 30 microliters or less) of fluid 20 that has been dispensed. Thus, the fluid 20 is substantially captured between the two surfaces and provides a "liquid bearing" surface in the contact zone between the two surfaces. This "liquid bearing" surface protects the material 16 from direct and potentially abrasive contact with the side surface 28 of the membrane 12. In addition, because the fluid fills the potential gap between the slide surface 18 and the side surface 28 of the membrane 12, no additional gapping mechanism is required and the accuracy with which the slide 10 must be positioned relative to the membrane 12 can be decreased.

[047] The forces acting on the fluid are controlled by the weight of the slide 10, which is fixed, and the aspect (orientation) of the slide relative to the base. These forces can be precisely controlled over a narrow loading range and a range of fluid volume can be used to resist these forces and form the "liquid bearing" surface. The range of useable fluid volume that can be captured between the slide surface and the base (or membrane) surface to form the "liquid bearing" surface is a function of fluid surface tension, surface energy of the contacting base surface, surface energy of the first surface of the slide and the contacting area between the slide and base. However, it also should be understood that the volume of fluid dispensed will also determine to some extent the width of the gap in which the "liquid bearing" surface is formed. The greater the amount of fluid dispensed into the gap, the wider the gap, up to the point where the fluid is no longer held within the gap by the forces that act to capture the fluid. For example, if the volume of dispensed fluid 20 is about 30 microliters, the gap will be smaller than if, for example, a volume of dispensed fluid 20 is about 100 microliters.

[048] There are a number of advantages associated with using small volumes of fluid for each fluid treatment. Antibody and nucleic acid reagents and other similar treatment fluids are typically expensive and the reduction of the volume of fluid required for each application can significantly reduce costs. Moreover, less rinse fluids are required to fully rinse the reagents from the slides. In addition, the reduction of reagent and rinse fluid volumes greatly reduces the complexity of fluid recapture and waste disposal.

[049] If the particular application requires that the material 16 be incubated for a specified amount of time with the fluid in contact with the material 16, the slide 10 can remain in the position FIG. 2C for the length of time required, if desired. Because of the capillary forces acting on the fluid 20, the fluid 20 will remain trapped between the first surface 18 of the slide 10 and the side surface 28 of the membrane 12. Moreover, if desired, slide 10 can be reciprocated up and down one or more times to release any air bubbles captured in the gap, to redistribute the fluid and/or to ensure that the material 16 is sufficiently covered with the fluid 20. Slide 10 can be reciprocated up and down between any two positions of engagement, such as between the position shown in FIG. 2B and the position shown in FIG. 2D. Reciprocation of a slide 10 between two positions refers to reciprocation between any portion of those two positions. As long as the slide 10 maintains a zone of contact of a sufficient size with the membrane 12, the fluid 20 will remain captured between the slide 10 and membrane 12. Alternatively, the material 16 can be incubated at a location away from the treatment station as described below.

[050] As shown in FIG. 2D, as the slide 10 moves upwards, the fluid 20 remains captured by the lower portion 22 of the slide. From the slide position shown in FIG. 2D, the slide 10 can be moved back to the position shown in FIG. 2C. The slide 10 can be reciprocated between the positions shown in FIG. 2C and FIG. 2D (or any positions between these two positions) as many times as desired.

[051] When the fluid treatment has been completed, slide 10 can be returned to the starting position (FIG. 2A) and be substantially or completely disengaged from the membrane 12 as shown in FIG. 2E. As the slide moves upwards, a greater portion of its surface area disengages from the side surface 28 of the membrane 12. The fluid 20 remains in contact with the membrane 12 in a shrinking capillary zone until the fluid flows downward out of the capillary zone. Thus, as the slide 10 is substantially disengaged from the membrane 12, a substantial portion of the fluid 20 has collected at or near the upper portion of the side surface 28 (FIG. 2D) and, fluid 20 can begin to flow down the vertical side surface 28 (FIG. 2E), particularly upon complete disengagement of the slide 10. It should be understood that the fluid 20 can be released from the gap without needing to completely disengage the slide 10 from the side surface 28. Also, if desired, slide 10 can be moved horizontally (or substantially horizontally) to further facilitate release of fluid 20. Thus, slide 10 can be moved laterally away from the side surface 28 or, alternatively, it can be tilted so that a lower portion of slide 10 moves away from the side surface 28. As shown in FIG. 2E, a collection device 40 can be positioned beneath the side surface 28 of membrane 12 to collect the falling fluid 20 for disposal or reuse.

[052] As discussed above, after treating the material sample with the volume of fluid, the slide can be disengaged from the treatment station so that at least a portion of the applied volume of fluid 20 is released from the gap between the slide surface 18 and side surface 28 of the membrane. Another portion of the applied fluid can remain on the surface 18 of the slide 10 forming a thin film thereon. The thin film of fluid remaining on the slide 10 after disengagement from the treatment station is desirably located only on the surface of the material sample, which provides a surface having sufficient attraction to maintain the thin film. Thus, in FIG. 2E for example, the thin film can be schematically represented by the same element as the material sample (element 16 in FIG. 2E), since the thin film desirably substantially covers the entire surface of the material sample 16. Of course, it should be understood that the thin film can cover less than the entire surface of the material sample. In addition, if the fluid is sufficiently viscous, the thin film can also cover (at least temporarily) a portion of the slide surface 18 other than where the material sample is located. As discussed in more detail below, the slide 10 can move to an incubation area with the thin film of fluid thereon and/or the thin film can be rinsed from the slide 10.

[053] FIG. 3 illustrates another embodiment in which fluid can be dispensed horizontally (or substantially horizontally) relative to top surface 30 of the membrane by a fluid dispensing device 24. Fluid 20 can be horizontally dispensed with sufficient force so that it directly impacts the slide 10 from where it will flow downward into the wetting region where the slide 10 contacts or abuts the base 14 (or membrane 12). For example, the fluid 20 can be applied directly to the slide, at or below the location of the material 16, from where it flows into the wetting zone, creating the "liquid bearing" surface discussed above. Alternatively, fluid 20 can be horizontally dispensed so that the fluid 20 is directly received into the wetting region or on the rounded surface 32, from where it flows downward into the wetting zone. After fluid 20 is dispensed and is ultimately received in the wetting region, the slide 10 can be moved downward relative to membrane 12. After the liquid bearing surface is created, slide 10 can be reciprocated up and down, as shown by arrow 48 and as described with respect to FIGS 2A - 2E. [054] FIG. 3 also illustrates a membrane 42 that comprises a replaceable surface element. Membrane 42 can comprise, for example, a sheet or roll of material that is wound between a feed roller 44 and a take-up roller 46. Thus, membrane 42 permits fresh membrane surfaces to be advanced as necessary to provide a fresh surface for treatment. Additional details relating to replaceable surface elements can be found in U.S. Patent Publication 2005/0164374 (incorporated by reference herein).

[055] FIGS. 4 - 6 illustrate schematic views of automated mechanisms for transporting a plurality of slides in a vertical orientation to and from a base 14 (with or without a membrane) for fluidic treatment. Each slide 10 can be removably coupled to a slide clip 38, which is in turn removably coupled to a conveying device 50.

[056] Conveying device 50 can be configured to provide movement of slides 10 in a variety of manners. For example, as shown in FIG. 4, conveying device 50 can comprise a chain mechanism 52 powered by a motor (not shown). Alternatively, the driving mechanism that conveys the slides from one position to another can comprise other mechanical means such as a belt drive or a screw drive. In addition, the path slides travel on the conveying device can be other than circular or oval (as shown in FIG. 4). For example, the slides can be moved from one position to another in a substantially straight line as shown in FIG. 7.

[057] In the embodiment shown in FIG. 4, chain mechanism 52 moves a plurality of slides 10 from one position to another in the direction of arrow 54. Each of the slides 10 are coupled to a slide clip 38, which is coupled to an arm 56. Each arm 56 is coupled to the chain mechanism 52. Thus, movement of chain mechanism 52 causes corresponding movement of each of the plurality of slides 10 coupled to conveying device 50.

[058] Referring to FIG. 5, as a slide 10 approaches the base 14, the movement of the conveying device 50 can stop. The movement can be an indexing movement such that each individual slide is indexed to adjacent treatment positions. If necessary, the slide 10 can be lowered or raised to the desired height for application of a fluidic treatment. The raising and/or lowering of the slide 10 can be automated. Thus, for example, a stepper motor 58 or other mechanism can be configured to raise or lower the slides 10 to position them to receive the fluid treatment. In one embodiment, the conveying device 50 includes a stepper motor arm 60 that operates in connection with the stepper motor 58 to position the slide 10 in the desired location. Alternatively, as shown in FIG. 6, a stepper motor 58 and stepper motor arm 60 can be positioned at each individual arm 56, permitting each slide 10 to be raised and lowered independently of the other slides 10.

[059] Of course, it is the relative motion between the surfaces of the slide and base which causes the "liquid bearing" treatment of surfaces described above. Accordingly, the same actions described above can be achieved by holding the slide in a fixed position and moving the base up and down. However, since slides typically already require manipulation and motion control, it is more desirable to move the slides, rather than the base, to achieve relative motion between the surfaces of the slide and base.

[060] After the slide 10 has undergone fluid treatment, slide 10 can be raised up and moved away from the base 14. If desired, another slide 10 can then be moved into position adjacent to base 14 for treatment. A plurality of bases 14 (i.e., fluid treatment stations) can be positioned along the conveying device 50. Thus, multiple slides can be treated simultaneously, if desired, at different fluid treatment stations. In addition, a plurality of fluid treatments can be performed along the path of travel achieved by a single conveying device. Moreover, multiple conveying devices can be used and the slides can be transferred from one conveying device to another by any automated or manual mechanism.

[061] The fluid treatments described above are configured so that specific treatments occur at a specific "station." The number of slides that can be processed through any given system is controlled by the time it takes to perform operations (treatment) at each station, and the time for each treatment varies depending on the particular treatment being performed. Thus, new slides cannot be treated until the slides currently being treated are processed and moved away from the treatment station. Conventional fluid processing stations are generally configured to treat a slide with a fluid and then maintain the slide at the same location while it is incubated. However, slide incubation after fluid treatment is typically the longest part of a fluid treatment process and, therefore, slide incubation significantly influences the maximum processed slide throughput for any given treatment station. [062] Using the fluid treatments described herein (e.g., about 30 microliters or less of an applied fluid) enables one to more efficiently treat a slide with a fluid and subsequently incubate that slide after the fluid treatment. As shown in FIG. 7, slides 10 can be transported between one or more incubation garages, with one or more fluidic treatment stations (e.g., station bases) or other treatment or rinse areas positioned therebetween. For example, as shown in FIG. 7, fluid treated slides 10 can be transported from a first incubation garage 62, rinsed at a rinsing station, transported to a second treatment station where they are treated with different fluid reagent, and then transported to a second incubation garage 64. The slides 10 can be moved in the direction of arrow 68 and can be transported by any mechanical or electro-mechanical means, such as the conveying devices described above. Each incubation garage 62, 64 can be separately humidified if desired. For example, a water reservoir 66 (or other humidifying means) can be positioned within each incubation garage. Also, if desired, incubation garages 62, 64 can be configured to be substantially covered or enclosed so as to maintain desired conditions therein, such as temperature and humidity levels.

[063] As discussed above, after the slide is disengaged from the treatment station, a thin film of the applied fluid remains on the slide. Because the thin fluid film is desirably small (i.e., only a portion of the applied volume of fluid) and desirably relatively viscous, the slides 10 can be transported and incubated at a location away from the fluid treatment station. Thus, after receiving a fluid treatment as described herein, slides can be transported and garaged during an incubation phase without concern for fluid spillage due to gravitational effects or the acceleration effects involved in moving the slides to the new location. As shown in FIG. 7, slides 10 can move sequentially through the length of the incubation garages 62, 64. The length of the garage as well as the speed at which the slides are moved can be selected to provide sufficient time for slide incubation. After being incubated, slides 10 can be transported to another fluid application station and the process can be repeated. Alternatively, if desired or if the films are larger or less viscous, the slides can be treated with a fluid as described above and then oriented horizontally for transport to an incubation garage or other treatment, rinse, or storage location. [064] The slides 10 can undergo any of a variety of fluid or other treatments, either before or after being transported to the incubation garages 62, 64. Thus, various sequential fluid application stations can be provided. For example, a reagent treatment can be performed at a first treatment station and a rinse treatment can be performed at a second treatment station. Alternatively, the reagent treatment and rinse treatment can be performed at a single treatment station.

[065] Referring again to FIG. 7, a rinse fluid treatment can be performed at a station base 69. Rinse dispenser 70 (e.g., nozzle) can dispense a volume of rinse fluid 72 downward as shown in FIG. 7. Rinse dispenser 70 can be configured to dispense rinse fluid 72 towards base 69 in the same manner described herein for other fluid treatments. Alternatively, the rinse fluid can be directed at the slide 10 without the use of a base (either from above the slide, as shown, or from below the slide). A rinse fluid collection device 74 can be positioned beneath the rinse station to collect rinse fluid 72 (and any reagents or other fluids that are rinsed from the slide 10) as those fluids fall downward in the direction of arrow 76.

[066] Other processing steps can also be accomplished as the slides 10 move from one incubation garage to another. For example, the slides 10 can pass through an air knife or blotter station. As shown in FIG. 7, an air knife station can be provided to direct air 80 from an air knife 78 at a slide 10 to remove excess reagent or other treatment or rinse fluids from the surface of the slide 10.

[067] Various fluid treatment stations can be positioned between incubation garages 62, 64. For example, as shown in FIG. 7, base 14 can receive a reagent (e.g., fluid 20) and the slide 10 can be treated in the manner described above. As shown in FIG. 2E, reagent fluid 20 can be collected by a collection device 40 as the fluid 20 falls in the direction of arrow 82.

[068] The incubation garages described above can be relatively small, since they need only accommodate the treated slides and a humidification device. For example, a substantially enclosed (enchambered) incubation garage can comprise an area only slightly larger than the 1 x 3 inches slide dimension. With the slides vertically oriented, as shown in FIG. 7, the slides can be compactly incubated in the incubation garage. Thus, a 12-inch long incubation garage can accommodate about 75 slides, depending on the packing efficiency of the system. The incubation time of slides in an incubation garage can be modified as desired by adjusting garage length, packing efficiency, and/or line speed (i.e., the speed of the slides on the conveying device).

[069] FIG. 8 illustrates an embodiment in which a single station base comprises a plurality of spaced-apart fluid treatment stations. Base 14 can comprise, for example, a rod-shaped base with four treatment stations as shown in FIG. 8. In another implementation, base 14 can comprise a rod that is about ¹A inch in diameter and about 12 inches long. A 12 inch long base can be sufficient to accommodate about 8 fluid treatment stations and can be housed within a space that is approximately 13 inches wide by 3 inches high and 2 inches deep. The addition of corresponding fluid dispensing devices, however, may require some additional head space. The fluid treatment stations along base 14 in FIG. 8 are desirably separated from one another by a sufficient distance to prevent fluid carry-over or mixing between adjacent fluid treatment stations.

[070] A corresponding plurality of fluid dispensing devices (such as described herein) can be configured to dispense one or more treatment fluids to the plurality of fluid treatment stations shown in FIG. 8. The fluid treatment stations can be configured so that each slide 10 undergoes the same fluid treatment at the same time or the fluid treatment stations can be configured so that each slide 10 undergoes a fluid treatment that is different from the other slides. FIG. 8 illustrates a plurality of slides 10 positioned on a single arm 56 for treatment. Arm 56 can be configured to move all of the slides 10 up and down in an automated manner (for group treatment) or arm 56 can comprise individual mechanisms to move the slides 10 up and down independently of each other (for individual fluid treatment).

[071] As discussed above, FIG. 8 illustrates an embodiment where there are multiple fluid treatment stations on one base 14. The base 14 shown in FIG. 8 can also be configured so that a single slide moves from one treatment station on base 14 to another treatment station on base 14. For example, a single slide 10 can be positioned at a first fluid treatment station (such as the fluid treatment station on the left in FIG. 8) and be subjected to a first fluid treatment. After the first fluid treatment is completed, the slide 10 can be moved along the length of the rod-shaped base 14 to a second fluid treatment station (such as the second fluid treatment station from the left in FIG. 8) where it can receive a second, different fluid treatment. In this manner, a single station base can be configured to provide a plurality of sequential fluid treatments to a single slide.

[072] A single slide 10 can also be treated at a single base 14 without moving the slide laterally to a new treatment position along the base. If desired, for example, the slide and base can be rinsed prior to performing a second fluid treatment at a single treatment location. Alternatively, a membrane (as discussed above) can be replaced and/or adjusted to provide a fresh surface for a second fluid treatment.

[073] In other specific embodiments, the station base can include a heating and/or cooling device, such as a resistive heater coupled with or integral to the station base, a radiant heater configured to heat one or more surfaces (such as the side surface) of the base station or a Peltier device coupled with or integral to the station base. Thus, for example, one or more slides can be treated at a station base and then heated or treated at the same location. In addition, one or more station bases can be enclosed in one or more covered or sealed chambers, within which one or more chambers the environment (such as humidity levels, temperature and/or pressure) can be independently or simultaneously controlled. Each station base also can be modular. Thus, for example, a single station base can be a modular element that is substantially enclosed with an independently controlled heating device. In this manner, the modular element can receive one or more slides and the entire modular element can be inserted into a larger unit or housing, such as a carousel or other such slide receiving apparatus. U.S. Patent Publication 2003/0211630, the entirety of which is incorporated herein by reference, describes examples of housings that can receive and dispense fluid onto slides.

[074] In addition to the shapes and configurations described above, bases 14 of the treatment stations can be formed in a variety of other shapes and configurations. For example, the vertical surface of the base (or membrane) that contacts the slide surface can be lengthened or shortened from those shown herein. In addition, the width of the contact surface can be narrowed or widened. For example, the station base shown in FIG. 4 can be rotated 45 degrees so that only a side edge of the base contacts the slide as the slide moves downward. Thus, the fluid treatment method would involve a constant narrow contacting fluid strip and the slide could be reciprocated up and down over that the side edge. In such an embodiment, if necessary, in addition to up and down reciprocation, the slide can be moved laterally to ensure complete fluid coverage of the sample material being treated. Station bases can also be configured so that the side (contacting) surface is not entirely vertical. For example, instead of tilting the slide past the vertical position (as described herein), the side surface of the base can be angled greater or less than 90 degrees relative to the top surface of the base. Moreover, the properties of the treatment fluid itself can affect the desired and/or required shape and surface properties of the base. For example, a less viscous fluid will require a higher friction surface on the side of the base (or membrane) in order to capture and maintain the fluid in the potential gap between the slide surface and base (or membrane) surface. In addition, certain rinse treatments may require fluid volumes of larger than 30 microliters (e.g., about 30-100 microliters). Thus, it may be desirable to modify the shape of the base station to accommodate the larger volume of rinse fluid for such treatments.

[075] The vertical and substantially vertical configuration of the slides and treatment surfaces described herein provided many benefits and advantages. The vertical orientation of slides permits compact and efficient space utilization. That is, because the slides are oriented substantially vertically instead of horizontally, the footprint of the entire apparatus can be minimized. In addition, because the apparatus uses gravity to dynamically direct (via rounded surfaces, for example) a volume of fluid into the potential gap between the slide and base surfaces, the dispensing of fluid droplets (or particles) can be successfully performed without the need for great accuracy. Also, because the volume of fluid is "captured" in the potential gap between the slide and base surfaces, a small volume of fluid is sufficient to treat the slide surface. After treatment is completed, excess fluid can be easily removed from the slide by simply letting the fluid roll off the vertical surface of the slide, where it can be easily recaptured by a collection device for reuse and/or disposal.

[076] In view of the many possible embodiments to which the principles of the disclosed invention may be applied, it should be recognized that the illustrated embodiments are only preferred examples of the invention and should not be taken as limiting the scope of the invention. Rather, the scope of the invention is defined by the following claims. We therefore claim as our invention all that comes within the scope and spirit of these claims.

Claims

We claim:

1. An apparatus for treating a microscope slide with a thin film of fluid, the apparatus comprising: a station base having a side surface; a slide conveying device that receives a microscope slide having a material sample disposed on a first surface of the microscope slide, the slide conveying device being configured to move the microscope slide from a first position to a second position where the microscope slide is oriented substantially vertically; and a fluid dispensing device configured to dispense a volume of fluid while the microscope slide is in the first position, wherein at least a portion of the dispensed fluid contacts one or more of the first surface of the microscope slide and the side surface of the station base while the microscope slide is in the first position; wherein the portion of dispensed fluid is held in a gap between the microscope slide and the side surface of the station base when the microscope slide is in the second position, and the portion of dispensed fluid forms a liquid bearing surface between the material sample and the side surface of the station base.

2. The apparatus of claim 1 , wherein the volume of fluid dispensed by the fluid dispensing device is about 30 microliters or less.

3. The apparatus of claim 1 , wherein the volume of fluid dispensed by the fluid dispensing device is between about 30 and 100 microliters.

4. The apparatus of claim 1, wherein the microscope slide is positioned to abut the side surface of the station base in the first position, and the dispensed fluid collects in an area where the microscope slide abuts the side surface of the station base when the microscope slide is in the first position.

5. The apparatus of claim 1, wherein the gap is expandable, with the gap being smaller in the first position than in the second position.

6. The apparatus of claim 1, wherein a lower portion of the microscope slide contacts the side surface of the station base when the microscope slide is in the first position.

7. The apparatus of claim 1, wherein the station base further comprises a top surface, and wherein the side surface further comprises a substantially rounded surface at an area near the top surface.

8. The apparatus of claim 1, wherein the side surface of the station base comprises a substantially vertical surface.

9. The apparatus of claim 1 , wherein the station base is a horizontally oriented cylinder, with the side surface of the station base being rounded.

10. The apparatus of claim 1, wherein the slide conveying device is configured to reciprocate the microscope slide up and down between the first and second positions.

11. The apparatus of claim 1 , wherein the slide conveying device is further configured to disengage the microscope slide from the side surface of the station base, wherein microscope slide disengagement from the station base causes fluid to flow downward along the side surface of the station base.

12. The apparatus of claim 1, wherein the station base comprises a membrane covering on its side surface.

13. The apparatus of claim 1 , wherein the slide conveying mechanism receives and moves a plurality of slides.

14. The apparatus of claim 13, wherein the side surface of the station base treats a plurality of slides simultaneously.

15. An automated apparatus for treating a plurality of slides with a thin film of fluid, the apparatus comprising: one or more treatment stations comprising a station base that has a side surface; one or more slide conveying devices configured to receive a plurality of microscope slides, each microscope slide having a material sample disposed on a first surface of each respective microscope slide, the one or more slide conveying devices being configured to carry the plurality of microscope slides and to move the microscope slides to and from the treatment station, the slide conveying device also being configured to move the plurality of slides up and down in a substantially vertical orientation between a first position and a second position; and one or more fluid dispensing devices provided at the one or more treatment stations, wherein, when one or more of the plurality of slides is positioned at the one or more treatment stations, the one or more fluid dispensing devices dispense a volume of fluid, the fluid being dispensed such that at least a portion of the dispensed fluid initially contacts one or more of the first surface of the microscope slide and the side surface of the station base and is captured therebetween; wherein movement of each respective microscope slide from the first position to the second position by the one or more slide conveying devices causes the at least a portion of the dispensed fluid to fill a gap between the first surface of the microscope slide and the side surface of the station base, the fluid filling the gap forming a liquid bearing surface that prevents the material sample from contacting the side surface of the station base.

16. The apparatus of claim 1 , wherein the volume of fluid dispensed by the fluid dispensing device is about 30 microliters or less.

17. The apparatus of claim 1, wherein the gap is expandable, with the gap being smaller in the first position than in the second position.

18. The apparatus of claim 15, wherein the slide conveying device is configured to independently move each of the plurality of microscope slides up and down between the first and second positions.

19. The apparatus of claim 15, the apparatus further comprising an incubation housing, wherein the slide conveying mechanism is configured to move the plurality of microscope slides from the treatment station to the incubation housing.

20. A method of treating a microscope slide with a thin film of fluid, the method comprising: providing a microscope slide with a material sample disposed on a first surface of the microscope slide; providing a station base having a side surface; providing a fluid dispensing device; positioning the microscope slide with the first surface of the microscope slide facing the side surface of the station base; dispensing a volume of fluid from the fluid dispensing device so that at least a portion of the dispensed fluid contacts one or more of the first surface of the microscope slide and the side surface of the station base and is captured therebetween; and moving the microscope slide downward in a substantially vertical orientation along the side surface of the station base; wherein the movement of the microscope slide downward causes at least a portion of the dispensed fluid to contact the material sample and form a liquid bearing surface between the material sample and the side surface of the station base, the liquid bearing surface preventing the material sample from contacting the side surface of the station base while the microscope slide moves along the side surface of the station base.

21. The method of claim 20, wherein the act of dispensing fluid comprises the dispensing of about 30 microliters or less of fluid.

22. The method of claim 20, wherein the act of positioning the microscope slide with the first surface facing the side surface comprises moving the microscope slide so that a lower portion of the microscope contacts the side surface of the station base.

23. The method of claim 20, further comprising: reciprocating the microscope slide up and down while maintaining the liquid bearing surface of fluid between the first surface of the microscope slide and the side surface of the station base.

24. The method of claim 20, further comprising: disengaging the microscope slide from the side surface of the station base, wherein the disengagement of the microscope slide from the station base causes the fluid that was held in the gap to be released and flow downward along the side surface of the station base.

25. The method of claim 20, further comprising: providing an incubation housing for incubating a microscope slide that has received a fluid treatment; and conveying the microscope slide to the incubation housing.