JPH04228062A - Capillary tube inoculator and assemblage - Google Patents

Abstract

A capillary inoculator assembly is provided for inoculating multiple test sites with small, precise volumes of inoculum. The inoculator employed in the assembly includes a trough-shaped carrier and one or more rows of capillaries extending therethrough. The capillaries extend through one or more rows of projections which form the lower part of the carrier. They are completely filled by capillary action, and the inoculum is retained therein by forces of adhesion and surface tension. A test device may be employed in conjunction with the capillary inoculator and includes discrete test sites which are aligned with the ends of the respective projections. Each of the test sites may be provided with an absorbent material such as a cellulose disk. A dry reagent may be deposited upon each disk so that the inoculum may be analyzed by testing equipment or by visual observation. A method is provided which includes the steps of filling the capillaries, aligning the capillaries with the test sites within the test device, and depositing the liquid inoculum on the respective test sites through wicking action or other procedures. A method is also disclosed for providing a plurality of discrete, liquid samples having small, precise volumes from a quantity of liquid which may be of indeterminate volume. <IMAGE>

Description

[Detailed description of the invention]

0001

FIELD OF THE INVENTION This invention relates generally to inoculators for inoculating test specimens with small volumes of liquids or suspensions.

0002

BACKGROUND OF THE INVENTION Many laboratory methods in the fields of microbiology and chemistry require the division of a liquid sample into small portions of known and usually equal volume. The most common method for dividing and depositing such samples is single-channel pipetting.
el pipetting). In this method, a liquid sample is drawn into a disposable tube or pipette and dispensed in a single volume or smaller, usually equal volumes. The technician must position the pipette tip over each test specimen and dispense the appropriate amount of sample into or onto the pipette. Care must be taken to avoid contact of the pipette tip with the test specimen as this may cause mixing. Furthermore, when such contact occurs, the volume of liquid within the pipette is lost.

[0003] Inoculating a large number of test specimens when using a single-groove pipette is a tedious operation. Although multi-channel pipette assemblies containing multiple tips can be employed to reduce the number of steps required to inoculate every specimen, tip contamination remains a concern and tip positioning is even more difficult. . Single or multi-channel pipettes are typically used to deposit very small samples in the range of 3-5 microliters, as they are not very repeatable.

A second group of devices used to deposit small and usually equal volumes of liquid samples is generally the Steers Replicator.
rs). Such replicators include a hand-held body that includes an array of pins projecting downwardly from the body and arranged as required for the intended inoculation method. Each pin has a blunt, concave or perforated tip. When the tips of the pins contact the liquid sample, the bottom surfaces of each pin retain a specific amount of liquid due to surface tension. These tips are then moved into contact with the test specimen, which is inoculated as the liquid is transferred. The actual amount of liquid transferred to the test specimen depends on the material forming the pin, the surface tension of the liquid, the substances present in the test specimen, and evaporation into the room air. This type of replicator may also allow air to escape since the geometry of the tip often does not allow air to escape once liquid is attached to the tip. In addition to being cumbersome and providing reasonable accuracy, the liquid sample to be transferred by the replicator must first be poured into a flat tray so that the pins are immersed therein. The tray must then be carefully positioned to avoid spills. Replicators are most commonly made of stainless steel and are therefore non-disposable. Therefore, the replicator must be sterilized once it has been inoculated with the test specimen.

Various disposable inoculation devices have been provided for inoculating test specimens containing various substrates used to identify microorganisms. One such device is disclosed in US Pat. No. 4,808,316. The apparatus includes a substantially rigid planar frame, a plurality of test recesses, a fill manifold in fluid communication with the test recesses, and a vent manifold in fluid communication with the test recesses. including. Each test well contains a suitable reagent capable of reacting with the liquid sample deposited therein. The liquid sample is delivered to the test well by gravity feed through the filling manifold.

Vacuum filling techniques for filling test recesses in comb members are disclosed in US Pat.
, 207,394 and 4,318,994. Each test well contains some combination of culture medium, antibiotic and indicator reagent. The microbial suspension is drawn into the test well by removing most of the air from the cavity. The liquid is then drawn in when atmospheric pressure is restored. Light transmission readings of the test wells are taken through the thickness of the panel.

One of the problems encountered when conducting medical tests is that the amount of specimen is often small. There is a need for a compact device for dispensing small volumes of specimens to test panels.

One such device has recently been developed that involves the use of a plurality of disc-shaped or other shaped supports on which dried reagents are deposited. The support can be made of alpha cellulose, neutral glass fibers or other such absorbent materials. Such supports may be attached to a carrier, such as a card or other surface support, or may be positioned within a test recess formed within the tray. In either case, it is important to inoculate each supporting specimen with the correct amount of analytical material so that the test is accurate and repeatable from surface to specimen and from test to test.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide an inoculator for inoculating a test specimen with a small volume of liquid or suspension, which solves the problems of the conventional devices. .

0010

SUMMARY OF THE INVENTION The inoculator of the present invention includes a carrier including a base and a sidewall defining a reservoir, and a plurality of carriers extending through the base of the carrier and in fluid communication with the reservoir. It consists of a capillary tube. Preferably, each capillary tube is formed as a hole in and extending through the base.

Preferably, the base of the carrier includes a plurality of projections each having a capillary tube extending therethrough. The protrusion has a beveled end, such as the conical end commonly used as the dispensing end of a pipette, to provide good retention of the liquid within the capillary while facilitating transfer of the liquid to the test specimen. Preferably, a portion is formed. By using the protrusion, the capillary can be filled by dipping the protrusion into the reservoir. If filling is accomplished in this manner, the carrier need not include the reservoir as an integral part. If an absorbent trap is incorporated into the carrier to absorb excess liquid, it is preferably provided adjacent to the reservoir.

Finally, an inoculator assembly is provided by the present invention, the assembly comprising a carrier having a plurality of capillaries extending therethrough and a test device positioned adjacent the carrier. , the test device includes a test specimen aligned with each capillary tube. Preferably, each test specimen comprises an absorbent support capable of drawing up liquid from each capillary tube by a wicking action. Preferably, a compressible member is installed between the carrier and the test device in order to separate the end of the capillary tube from the test specimen before starting the inoculation process. When pressure is applied to the carrier, it forces the end of the capillary tube into contact with the test specimen and transfers liquid to the test specimen. Preferably, the carrier includes a plurality of projections each having a capillary tube extending therethrough. Each protrusion is
Preferably, it is formed by a beveled end positioned in opposing relation to one of the test specimens.

The method of the present invention includes the steps of: providing a carrier with a plurality of capillaries extending therethrough; providing a liquid within each capillary; and aligning the capillary with a plurality of test specimens. , transferring the liquid in each capillary to each test specimen. Such liquid transfer is preferably accomplished by moving the carrier towards the test device until a capillary tube contacts each test specimen. Preferably, each test specimen is provided with an absorbent substrate that wicks liquid from each capillary by a wicking action.

[0014] Also provided is a method of filling an inoculator of the type that includes a carrier and a plurality of capillary tubes extending through the carrier to provide a plurality of discrete liquid samples. The method includes contacting the capillary tubes with a liquid and substantially completely filling each capillary tube. The capillary tube is partially or completely filled by capillary action. By capillary action or a combination of gravity feeding and capillary action, the amount of liquid entering each capillary is precisely controlled by completely filling the capillaries in this way.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An assembly 10 for inoculating a test specimen that is accurately reproducible and has an arbitrary volume equal to a suspension or other liquid sample is provided by the present invention. The assembly includes an inoculator 12 and a tester, which may be in the form of a panel 14 that is associated with the inoculator. A compression member, such as a foam gasket 16, is disposed between the inoculator 12 and the test panel 14, which compresses the tester and inoculator into a suitable position when the gasket is in the "relaxed" state. Separate by distance.

The inoculator includes a generally tub-shaped carrier 18, which is preferably of monolithic construction and molded from a transparent polymeric material such as polystyrene resin. It is important that the resin has high purity and that no silicone mold release agent is used in the molding process. This is necessary to provide an inoculator with a clean surface of controlled hydrophobicity, the importance of which will be discussed below.

Carrier 18 has a base 20 that includes a generally planar upper surface 22, a peripheral side wall 24 projecting from upper surface 22, and two rows of capillary tubes 26, the base and side walls defining a reservoir or trough. Define. Each capillary tube extends into the base and has a top surface 2 of the carrier base.
2 and in fluid communication with the reservoir. Filling of the capillaries is facilitated if these capillaries are sloped relative to the side walls 24.

Extending from the lower surface of carrier base 20 are two protruding strips 28 . Each protrusion includes an angled end 30 adjacent the bottom opening of each capillary. These beveled ends of the protruding strips, together with the carrier base 20 and the protruding strips, define the walls of each capillary tube 26 and are useful for maintaining liquid within the capillary tube. Although it is possible to employ flat bottom protrusions or even no protrusions, in this case the flow of liquid within the capillary tube is encouraged and the suspension on each flat bottom surface is A droplet is formed. The preferred beveled edges allow liquid to flow back up from each beveled edge so that nothing can happen. A second advantage of the beveled protruding ends is that while the capillary and the test specimen are brought into contact and engagement, these beveled ends increase the likelihood that the capillary will make proper contact with the test specimen, and this method is detailed below. It is important that the bottom surface of the tip of the protrusion is not significantly more wettable than the inner wall of the capillary, since the inoculum will flow through the capillary and potentially contaminate the reaction area or specimen.

The capillaries in a single inoculator each have approximately 1 to
They can have the same or different volumes in the range of 25 microliters. Inoculator 12 shown in Figures 1-5
is designed to inoculate 64 disk-shaped supports 32 with the same volume of liquid or suspension. (The terms liquid and suspension are used interchangeably herein.) The support may be in the form of an absorbent plate, a hydrophilic membrane or other material depending on the test being performed. good. Microwells may be seeded with liquid from each capillary. Each capillary is attached to the upper surface of the carrier base 2
Approximately 0.140 cm (0.055 inch) in diameter at 2
from the opening end of each protruding strip 28 to approximately 0.102 cm (0.
040 inches). The length of each capillary is approximately 0.30 cm (0.12 inches), so its volume is approximately 3.5 microliters.

The capillary tube of the inoculator 12 used in the preferred embodiment of the invention is provided with such an angled, preferably conical inner wall 34 to facilitate the inoculator shaping process. Without a drafting angle, the elongated central pin on the scale of the capillary tube can be pulled out of the capillary molded part without damaging the capillary tube and without eroding the pin. Although not required in the inoculator 12 shown and described herein, a capillary tube that is larger at the top than at the bottom ensures that a larger volume of liquid can be held than one having a uniform diameter. The range of acceptable capillary diameters depends on the material properties of the capillary and of the liquid held within it, the range of accelerations at which the capillary is expected to hold liquid due to surface tension, the manner in which the inoculator is filled with liquid, and the inoculation. It depends on the method used to remove the liquid from the vessel. In a preferred embodiment of the invention, liquid is removed from each capillary tube 26 by wicking into a small absorbent support containing a reagent that reacts with the liquid. When using this extraction method, the minimum diameter of the capillary base must be several times larger than the effective pore size of the absorbent support. For the specific support described below, 0.00254c
A minimum diameter of 0.001 inch (m) is acceptable. However, such small diameters are difficult to mold and unduly retard removal of the desired liquid. In other applications,
There are no clear lower limits other than those imposed by the method of manufacturing the container and the required rate of liquid withdrawal.

The maximum diameter of the bottom of each capillary tube 26 is
It is determined by the need to retain liquid within the capillary tube during the acceleration associated with the desired movement of the inoculator 12 between when the inoculator 6 is filled and when liquid withdrawal is required. The surface tension at the surface of the liquid must overcome the resulting acceleration. In a preferred embodiment of the invention, an aqueous solution containing a low concentration of wetting agent is held within a polystyrene capillary tube having a length several times (i.e. 2 to 4 times) the average diameter. The upper limit of the diameter of each capillary tube is practically about 0.254c
m (0.1 inch). even slower movement of the inoculator,
For more torturous capillary materials and higher surface tensions, larger diameters can be used. These maximum diameters also depend on the length of the capillary and the direction and magnitude of the acceleration. The greatest force that must be opposed is generally gravity.

[0022] The maximum diameter of the tip or liquid inlet end of the capillary is limited by the volume accuracy desired when the capillary is filled by flowing liquid across it; This is the preferred filling method employed for the disclosed contactor. If the diameter becomes too large, volumetric accuracy will be compromised due to changes in the surface shape of the liquid left behind when the flowing liquid separates from the liquid held within a particular capillary.

If desired, the capillary tube may be filled from the bottom by capillary action. The prongs are immersed in the liquid for a sufficient amount of time to completely fill the capillary. Preferably, the capillaries are filled at the same time. In this case, the maximum diameter of the top (and all other parts of each capillary) is subject to the requirements that the surface tension of the liquid, the contact angle with the material of the capillary and the diameter ensure that each capillary is filled to the top. . This provides volumetric accuracy.

The transparent polystyrene carrier adopted here and used with the microbiological suspension for the inoculum absorbent support works well when each capillary has a volume of 3 to 10 microliters. do. 1 to 25 when using different materials and/or design parameters
Capillary volumes in the microliter range can be employed. Generally, capillaries are filled with the same volume of liquid within 10 minutes or less prior to transfer, such that the volume of liquid held within each capillary is not suddenly released or significantly evaporated; It is designed to have the same volume as when it is held. These objectives can be successfully achieved when using the parameters described above.

In FIGS. 1, 2 and 4, the inoculator 12 includes a carrier designed in the form of an elongated tub with an elongated central protrusion 36 separating two rows of capillary tubes 26. . (Protruding strips 36 should be omitted if they make it difficult to fill the capillaries.) One end of the carrier is provided with a filling area 38 free of capillaries. The fill region 38 has an angled top surface 40 that joins the top surface 22 of the carrier base 20 at one end and the surrounding side surfaces 24 on three sides. Accordingly, the liquid deposited on the top surface 40 of the filling area is absorbed by the capillary tube 26.
It tends to move toward the top surface 22 of the carrier base 20, which includes the top opening.

A trap 42 for excess inoculum is attached to the carrier base 20 in a spaced relationship to the rest of the reservoir.
It is formed by integrating with. A second protruding ridge 44 including an angled surface 46 that joins the main storage section separates this storage section from the trap 42 . Inside the trap,
A sponge 48 or other absorbent material is placed. Any absorbent material may be employed within the trap so long as it does not release dirt or fibrous debris into the capillary region and is not affected by the inoculum.

A pair of laterally extending flanges 50 project from each side of carrier base 20. One of these flanges includes a relatively large area 52 that can be used to grip the inoculator and/or apply an identification label.

A plurality of legs 54 protrude downward from the bottom surface of the carrier 18. The legs raise the tip of the capillary tube out of contact with the active surface and serve as a positioning device for aligning the inoculator with the test panel when the capillary tube is attached to the plate described below.

A clear cover tape 56 made of adhesive-backed clear Mylar or other liquid impermeable material is attached to the upper edge of the peripheral wall 24 of the carrier 18. The tape covers all parts of the carrier except the fill area 38.

The structure and shape of the device to be inoculated by the contactor 12 according to the invention depends on the particular application of the device. Several such devices are disclosed in U.S. Patent Application No. 209,677, filed June 20, 1988, entitled "Apparatus for Promoting Fluorescence and Kinetics and Methods of Using the Apparatus." , which is incorporated herein by reference.

As shown, test panel 14 is molded from polypropylene or other suitable polymeric material. As shown in FIGS. 1 and 4, the test panel includes a generally flat rectangular body 58 having a flat top surface 6.
It has an elongated protruding strip 60 having a diameter of 2. Sixty-four cylindrical test recesses 64 are provided, each having an upper opening that joins the top surface 62 of the elongated bar and a lower opening that joins the bottom surface 66 of the test panel. The diameter of each recess is
It is larger than the diameter of the protruding strip 28 extending from the inoculator. The depth of the recess 64 is shallower than the length of these protruding stripes. Randomly positioned reference notches 68 are provided on the longitudinal edge of the test panel closest to the recesses, each notch being aligned with one of the respective recesses. A plate-shaped data label 70 may be attached to the top surface of the test panel.

A transparent, liquid-impermeable adhesive tape 72 is affixed to the bottom surface of the test panel 14. The tape may be an acrylic, adhesive-backed strip made of clear Mylar or other suitable polymeric material. As shown in FIG. 4, tape 72 is secured to bottom surface 66 of test panel 14. Tape 72 provides an adhesive bottom for each of cylindrical recesses 64. A disk or membrane 32 is attached to the adhesive bottom of the cylindrical recess 64 and comprises a test specimen where test data is obtained.

A notch 72 is provided in one of the ends of the test panel 14 for receiving one of the legs 54 extending from the inoculator 12. Test panel 14 to receive the other two legs 54 of the inoculator.
Two openings 74 are formed near opposite ends of the . The test panel itself may have multiple legs 76 to facilitate its handling, position it within the device, and protect the transparent tape. A ventilation groove 78 extends between the end of the elongated bar 60 and the edge of the test panel.

The disc-shaped support 32 within each cylindrical test well 64 is preferably made of an absorbent material such as alpha cellulose or neutral glass fiber. Particularly preferred is alpha cellulose in the form of cotton lint paper. The thickness of the disc should be sufficient to carry an effective amount of reagent for reaction with the particular fluid inoculum. Generally, when the support is a multi-piece filter paper, the diameter is 0.2 mm to
A thickness of 2.0 mm was found to be appropriate. In such cases, the test reagent solution is absorbed and dried by the support prior to receiving the liquid inoculum from inoculator 12. Generally, a support thickness of 0.5 mm to 0.9 mm is preferred for such analysis.

The shape of the support within each test recess 64 is not critical. The thickness of the supports, along with their surface area, determines the volume of liquid required to completely wet each support. Preferably, the pore volume of each support is between about 1 microliter and 25 microliters.

In operation, liquid inoculum is introduced into the reservoir of carrier 18 by pouring or pipetting into filling area 38 . A preferred feature of the invention is that the sample volume introduced into the inoculator may be varied over a wide range, e.g. from 300 to 1000 microliters, without affecting the accuracy of the volume deposited on the test specimen. .

The liquid inoculum collected within the carrier will generally not have sufficient volume to cover the entire capillary tube upon introduction. Due to the hydrophobic surface defining the reservoir, the liquid inoculum forms a rotating volume that covers only about 1/4 of the capillary. However, no additional liquid is required to avoid consumption of the inoculum. Filling area 3
After all of the liquid inoculum has been collected in 8, the operator tilts the inoculator 12 slightly towards the end of the trap and subsequently moves this amount of liquid over the top of the capillary until the capillary is covered with liquid. Each capillary is filled when Filling occurs partially by gravity flow, but primarily by capillary action. The two troughs defined by the side walls 24 and the elongated protrusions 36 must be sufficiently narrow to fill each capillary as the liquid passes over them. If no protruding strips are employed, the distance between the side walls must be small enough for the liquid to engage the capillary tube. Once all the capillaries are filled and excess liquid is located at the end of the trap, the inoculator is tilted 30-40° about its longitudinal axis towards the trap 42 to direct the liquid past the protruding strip 44. It flows into the trap sponge 48. The hydrophobic surface of the carrier essentially does not retain liquid in the grooves above the capillaries. Cover tape 56 helps prevent spills.

Preferably, the liquid collected within the capillary inoculator 12 contains a visible dye to ensure that all capillaries are completely filled. When viewed from the top of capillary tube 18, the space within the capillary tube is relatively long and narrow. Therefore, it is easily visible with small amounts of dye, and partially filled capillaries are visually lighter in color.

Alternatively, by choosing a liquid with the same refractive index as the plastic forming the capillary,
Eliminates the need to use dyes. In this case, instead of looking for a column of relatively dark liquid to ensure each capillary is filled, the capillary pores disappear when filled.

The inoculator 12 is preferably, but not necessarily, attached to the test panel 14 prior to filling. Foam gasket 1 placed between the inoculator and the test panel
6 or other resilient separating means should be sufficiently rigid to prevent contact between the protruding strips 28 and the disc-shaped support member 32 during normal handling. Furthermore, the capillary tube itself should be of an appropriate size and shape so that the liquid does not slosh around during normal handling, including raising or lowering the inoculator.

Preferably, the transfer of liquid from the inoculator 12 to the test specimen within the test panel 14 is mechanically initiated. As shown in FIG. 5, a self-aligning plate (not shown) is pressed onto the top of the inoculator, thereby bringing the tip of the capillary tube into contact with support member 32. If the support member is sufficiently absorbent, when such contact occurs, liquid will be drawn up from the capillary rapidly and almost simultaneously. Although a similar process can be performed manually, it is important for many applications that a machine read be made immediately after inoculation. With manually initiated inoculations, repeatable tests cannot be performed uniformly and uniformly. As mentioned above, inoculation can also be achieved by compressing gas at the top of the capillary or by suddenly accelerating the inoculator.

Depending on what reactive material is incorporated into each support member 32, appropriate tests can be performed following inoculation. The reaction between the inoculum and the reaction material can be observed visually in some cases. It is not critical to inoculate the test specimen immediately after filling, since the liquid does not easily evaporate from the capillary. A foam gasket 16 protects the tip of the capillary tube from air flow, while a protective tape 56 protects the top opening of the capillary tube. Therefore, evaporation is minimized.

Machine readings are taken with the inoculator in the position shown in FIG. Alternatively, the inoculator may be removed from the test panel and discarded.

If desired, a sponge 38 or other absorbent material disposed within the inoculator can also contain reagents dried thereon. If excess inoculum is allowed to flood into the trap, a large amount of analyte can be brought into contact with the reagents. To indicate a positive result,
A visible color change or fluorescent reaction can be used. The method can be used for tests performed on test specimens in test panels 14 that do not require relatively large but precise volumes, but require small, precise samples.

The inoculator and inoculation method described above offer a number of important advantages in situations where small, precise amounts of liquid inoculum must be deposited onto a test specimen. No compression or suction is required to move the inoculum, thus avoiding errors associated with air compression. High positional and volumetric accuracy is not required when filling the inoculator with a single pipetting stroke or injection motion. A single action divides the inoculum into multiple volumes. The individual volumes of inoculum are independent of each other, so that mixing with each other is avoided when the inoculum is transferred to the test specimen. Excess inoculum is collected in the inoculator, thus preventing spillage, accidental contact and errors in the amount of inoculum. By using the inoculator in the manner described above, good precision and repeatability can be obtained even when test specimens having a volume of 5 microliters or less are inoculated simultaneously. The inoculator can visually determine whether the capillary has been filled correctly and that the liquid in the capillary is not significantly affected by evaporation during the normal time between capillary filling and inoculation. is ensured. Liquid is retained within the capillary tube regardless of the orientation of the inoculator.

Another embodiment of the invention is shown in FIGS. 6-7. The assembly 10' shown here generally corresponds to FIGS. 1-5.
It has the same structure and function as the one shown in , but is suitable for handling relatively small volumes of liquid.

The assembly includes an elongated inoculator 12' and a test device 14' associated with the inoculator. Inoculator 1
2' can be engaged to the test device 14' by means of a common coupling snap (not shown) integrally formed on each part. A pair of resilient clasps 16' positioned between the inoculator 12' and the test apparatus 14' on opposite sides of the assembly 10' maintain the inoculator 12' in the raised position shown in FIG. Ru. Only one of the fasteners is shown in FIG.

By using a fastener 16' instead of a foam gasket 16, air can be allowed to pass through the assembly. To minimize losses due to evaporation, the inoculator 12' is formed by a wall member 17' that fits within a generally oblong groove 19' around the test recess 64' in the test apparatus 14'. . These wall members 17' and the outer wall 21 of the test recess 64'
The relative position of ' prevents air flow across the bottom of capillary tube 26 ', thereby reducing evaporation that would otherwise occur.

Inoculator 12' has a carrier 18' that includes a flat top surface 22' and a peripheral sidewall 24' projecting from the flat top surface. The carrier 26' is substantially abutting against the side wall to facilitate liquid inflow. No protruding striations are provided between the rows of capillaries. A flange 52' is also provided which has a structure and function similar to flange 52 in the embodiment shown in FIGS. 1-5.

Test apparatus 14' is similar in construction to the embodiments described above, with some exceptions noted above. Further, the disk-shaped support member 32' is attached to the tape 72 described above.
rather than to the bottom surface of the test device itself. Filling the inoculator 12' and inoculating the test specimen is accomplished in much the same manner as described above with respect to the initially mentioned inoculator 12. The inoculator 12' is filled while in the position shown in FIG. 6, and inoculation occurs when the inoculator is moved to the position shown in FIG. When the projections 28' contact the absorbent test specimen, substantially all of the liquid within each capillary tube 26' is dispensed.

Although the embodiments of the present invention have been described herein with reference to the accompanying drawings, the present invention should not be limited to these embodiments only, and there may be It will be appreciated that various other modifications and improvements may be made by those skilled in the art.

[Brief explanation of the drawing]

FIG. 1 is an exploded view of the inoculator and test panel of the present invention.

FIG. 2 is a plan view of the inoculator of the invention shown in FIG. 1;

FIG. 3 is a side view of the inoculator of the present invention shown in FIGS. 1 and 2.

FIG. 4 is a cross-sectional view of the inoculator test panel assembly of the present invention in a first position with respect to each other;

FIG. 5 is a cross-sectional view of the inoculator test panel assembly of the present invention in a second position with respect to each other.

FIG. 6 is a cross-sectional view of another embodiment of an inoculator of the invention positioned on a test panel.

FIG. 7 is a cross-sectional view of the inoculator of the present invention in engagement with a test panel. 10 inoculator assembly, 12
inoculator, 14 test panel, 16 foam gasket, 18 carrier, 20
carrier base, 26 capillary, 3
2 Support member, 42 Trap, 48
sponge, 70 data label, 72 tape,

Claims (12)

[Claims] 1. A capillary inoculator for dividing a liquid inoculum into a plurality of volumes and inoculating a plurality of test specimens, comprising a base, a side wall projecting upwardly from the base, and optionally a side wall projecting upwardly from the base. a carrier including a cover attached to the carrier, the base and sidewalls defining a reservoir; and a plurality of capillaries in fluid communication with the reservoir, each capillary tube extending through the base. , each capillary tube being capable of holding therein a liquid inoculum subject to at least gravity by surface tension and adhesive forces. 2. The base and the sidewalls define an elongated reservoir including a pair of opposing ends and an overflow trap, and includes means for separating the reservoir from the overflow trap. 1. The capillary inoculator according to 1. 3. A capillary inoculator for inoculating a plurality of test specimens, comprising a carrier, a plurality of protrusions extending from the carrier, and a plurality of capillary tubes extending through the protrusions. a plurality of capillaries, each capable of holding therein a liquid inoculum subjected to at least gravity by surface tension and adhesive forces, each having a pair of open ends such that it can be filled by capillary action; , a capillary inoculator consisting of. 4. The capillary inoculator of claim 3, wherein each of the projections has a beveled bottom end. 5. An assembly for inoculating a plurality of separate test specimens simultaneously, the inoculator comprising a carrier and a plurality of capillaries extending through the carrier, each of the capillaries comprising: an inoculator capable of retaining the liquid inoculum therein by surface tension and adhesive forces at least sufficient to overcome gravity, each of the capillaries including a discharge end; and a liquid inoculum from the inoculator; a device arranged adjacent to said inoculator to receive said inoculator, said device including a plurality of separate test specimens, each discharge end of said capillary tube being aligned with a respective said test specimen; An assembly comprising the above device. 6. A compressible member positioned between the inoculator and the device, the discharge ends of the capillaries each being compressible when the inoculator is moved a selected distance toward the device. Positioned in contact with the test specimen, the compressible member is compressed when the inoculator is moved the selected distance toward the device. An assembly according to claim 5. 7. The assembly of claim 5, wherein the carrier defines a reservoir in fluid communication with the capillary tube. 8. The assembly of claim 5, wherein a plurality of test recesses define test specimens within the device, each optionally including a plurality of absorbent supports positioned within the test recesses. . 9. A method for simultaneously inoculating a plurality of test specimens with a liquid inoculum, the method comprising: providing an inoculator including a carrier having a plurality of capillaries extending therethrough, each having a discharge end; providing a liquid inoculum in each of said capillaries, said liquid inoculum being retained in each of said capillaries by surface tension and adhesive forces at least sufficient to overcome gravity; and a plurality of tests. providing a test device containing a specimen and optionally an absorbent material; aligning said capillary tubes with said respective test specimens; and transferring said liquid inoculum in each of said capillary tubes to said respective test specimens. A method consisting of and. 10. A compressible member is provided between the inoculator and the test device, and the inoculator is biased toward the test device to compress the compressible member and discharge the capillary tube. 10. The method of claim 9, comprising contacting an end with each of said test specimens. 11. A method of providing a plurality of discrete liquid samples having small and precise volumes, the method comprising: supplying liquid into the reservoir; contacting each of the capillaries with the liquid for a period of time sufficient to substantially completely fill the capillaries. 12. A method of providing a plurality of discrete liquid samples having small and precise volumes, the method comprising: a plurality of protrusions extending therefrom; and a plurality of capillaries extending through each protrusion. and immersing the protrusion in the liquid for a time sufficient to substantially completely fill the capillary tube with the liquid by capillary action.