Patent Description:
<CIT> discloses a blood sampler with two septa.

The invention relates to a system for mixing a sample with a combined buffer including a sampler body, the sampler body including a first reservoir and a second reservoir according to claim <NUM>. The system further includes a first separator forming a first enclosure with the sampler body for the first reservoir. The system further includes a second separator forming a second enclosure with the sampler body for the first reservoir. The system further includes a third separator, in conjunction with the second separator, forming a third enclosure and a fourth enclosure, respectively, both in conjunction with the sampler body, for the second reservoir. Optionally, the first and third separators are foil. Alternatively, the second separator is a septum. In one alternative, the first reservoir includes a first buffer and the second reservoir includes a second buffer. The system further includes a blood collector, the blood collector including a piercing projection, and the blood collector shaped to mate with the sampler body, such that when the blood collector is inserted into the sampler body at an aperture in the sampler body, liquid cannot escape from the combination of the sampler body and the blood collector. Upon insertion of the blood collector into the sampler body, the piercing projection of the sampler body pierces the first and second separators. Optionally, the blood collector includes a capillary tube that holds the sample. Alternatively, upon insertion of the blood collector into the sampler body, the first and second buffers mix with the sample. Optionally, the sampler body includes a cylindrical cavity that houses the first and second reservoirs. In one configuration, the septum provides one pound of force resistance to piercing. In another configuration, the septum has four equal quadrants joined by a thin connector material. Optionally, the septum is molded plastic. Alternatively, the four equal quadrants are thicker that the thin connector material.

The invention also relates to a method for mixing a sample with a combined buffer according to claim <NUM> that includes providing a sampler body. The sampler body includes a first reservoir and a second reservoir. The sampler body further includes a first separator forming a first enclosure with the sampler body for the first reservoir. The sampler body further includes a second separator forming a second enclosure with the sampler body for the first reservoir. The sampler body further includes a third separator, in conjunction with the second separator, forming a third enclosure and a fourth enclosure, respectively, both in conjunction with the sampler body, for the second reservoir. The method further includes providing a blood collector, the blood collector including a piercing projection, and the blood collector shaped to mate with the sampler body, such that when the blood collector is inserted into the sampler body at an aperture in the sampler body, liquid cannot escape from the combination of the sampler body and the blood collector. The method further includes inserting the blood collector into the sampler body; advancing the blood collector and breaking the first separator; and advancing the blood collector and breaking the second separator. Optionally, the first reservoir includes a first buffer and the second reservoir includes a second buffer. In one alternative, the method further includes mixing the first and second buffers; and mixing a sample held in the blood collector with the first and second buffers by agitating the combined sampler body and blood collector. Optionally, the first and third separators are foil. Alternatively, the second separator is a septum. Optionally, the blood collector includes a capillary tube that holds the sample.

In another configuration, the septum has four equal quadrants joined by a thin connector material. Optionally, the septum is molded plastic. Alternatively, the four equal quadrants are thicker that the thin connector material.

Certain terminology is used herein for convenience only and is not to be taken as a limitation on the embodiments of the systems and methods for a multi-chambered sampler. In the drawings, the same reference letters are employed for designating the same elements throughout the several figures. A multi-chambered sampler uses a first separator and a second separator to hold two compartments of reagents. A sample collector is used to penetrate both the first and second separators. This allows for the mixing of a sample in the sample collector with both reagents.

In some point-of-care tests, a required buffer is stable in the short term (hours), but unstable in the longer term (weeks to months). These point-of-care tests typically involve a sampler, including a blood collector, a sampler body, and a sampler base, and a test cartridge or test strip for receiving a sample mixed in the sampler. In order to achieve long-term stability of the buffer and hence the product, the buffer should be prepared in two stable fractions and those fractions mixed to form the active buffer just prior to use. Embodiments of the multi-chambered sampler address the issue of managing the two stable fractions of the proposed buffer while continuing to be able to offer customers an easy-to-use sampler body system. The goal is to achieve a sampler design that would keep the unstable fractions separated until needed; then the standard action of the user inserting the blood-filled blood collector into the sampler body and subsequently shaking it would automatically mix the buffer fractions together with the blood, and the combination then could be dispensed into the test cartridge in the standard fashion.

Therefore, embodiments of a sampler are described herein that provide for two compartments for holding two buffers that are combined at the time of usage. This sampler is easy to use and merely requires the user to insert a mated blood collection device into the sampler.

<FIG> shows one example of a sampler body. Sampler body <NUM> includes an upper end aperture <NUM> for the insertion of a sample collector. As shown, the central storage area <NUM> is a single piece. In contrast, <FIG> shows an embodiment of a sampler body having a septum <NUM> or other separator in sampler <NUM>. This effectively divides the central reagent storage area with a septum that later can be broken by the blood collection device. A molded dual chamber sampler body contains a septum <NUM> that is strong enough to keep the two solutions apart during storage, but weak enough that the mechanical action of inserting the blood collector into the sampler body breaks the septum and allows the solutions to mix. <FIG> shows a view of a sampler body <NUM> cross-section with a single central chamber <NUM> (after the foil staking process), and <FIG> shows a view of a sampler body <NUM> cross-section with a single septum <NUM> splitting central chamber <NUM> into two chambers (after the foil staking process). The foil staking process will be explained in the subsequent figures; however, the top portion of central chamber <NUM> is typically foil covered to seal the reagent in the central chamber <NUM>. In both examples, the sampler body <NUM> includes an upper foil sealing surface <NUM> and a lower foil sealing surface <NUM>. The blood collector pierces this foil.

<FIG> show a sampler body <NUM> and a cross-section of sampler body <NUM>, along cross-section line B, respectively. <FIG> show a sampler body <NUM> and a cross-section of sampler body <NUM>, along cross-section line B, respectively. Here, septum <NUM> is visible. Septum <NUM> may be formed from a variety of materials such as plastics, foils, and other materials. As shown, septum <NUM> includes four equal sections that are separated by a thin joint of material that may easily rip and break when the blood collector is inserted. In the embodiment shown, septum <NUM> may be made of plastic as well as other materials.

<FIG> shows an example of a sampler body <NUM> with single buffer-filled chamber formed by foil heat staked ends that does not form part of the present invention. <FIG> shows an embodiment of a sampler body <NUM> with two buffer-filled chambers formed from molded-in septum and foil heat staked ends. As is shown, sampler body <NUM> includes a top foil closure <NUM> and a bottom foil closure <NUM>. A reagent <NUM> (in many cases, a buffer) is stored in the chamber between the top foil closure <NUM> and the bottom foil closure <NUM>. In sampler body <NUM>, a first reagent <NUM> is stored between a top foil closure <NUM> and the septum <NUM>. A second reagent <NUM> is stored between the septum <NUM> and the bottom foil closure <NUM>. Although the septum and closures are described as having specific properties, alternative materials and closures may be used in some embodiments. For instance, plastics, coated papers, and other materials that may be made thin enough to pierce may be utilized for the foil closures and, similarly, the same materials or foil may be used for the septum.

<FIG> show the progressive insertion of a blood collector into a septum-containing sampler body showing the opening of the septum through the insertion force of the blood collector. Current insertion force of the blood collector is about <NUM>-44N (five to ten pounds). Expected yield force of molded-in septum is about <NUM>. 4N (one pound force), so the user will be unaware of the added complexity of this sampler design. In <FIG>, a blood collector <NUM> is used to retrieve a sample, typically a blood sample resulting from a finger prick. Blood collector <NUM> includes a piecing tip <NUM> and a capillary tube <NUM> that holds a sample. As shown, blood collector <NUM> is aligned with the top aperture <NUM> of sampler body <NUM> that includes septum <NUM>. <FIG> shows the sampler body <NUM> advanced to the septum <NUM>. Because of the venting mechanism <NUM>, the force of air attempting escape should be at a minimum. Blood collector <NUM> mates precisely with sampler body <NUM> such that no liquid will escape during insertion as the foil and septum <NUM> are penetrated. <FIG> shows the piercing projection <NUM> advanced through the septum <NUM>.

<FIG> shows one view of an embodiment of the septum <NUM> after the piecing projection <NUM> has broken it. Although some material may remain, the fluid flow past septum <NUM> should be largely uninhibited after piercing.

<FIG> shows blood collector <NUM> fully inserted into sampler body <NUM>, breaking the heat staked top foil seal as well as molded-in septum <NUM>, allowing fluids in both chambers to mix into a combined reagent <NUM>.

<FIG> show another view of the insertion of blood collector <NUM> into sampler body <NUM>. As shown, blood collector <NUM> includes a piercing projection <NUM> and a capillary tube <NUM> containing a sample. The blood collector <NUM> aligns with the aperture <NUM> in sampler body <NUM> and may be inserted. Upon insertion, piercing projection <NUM> breaks foil <NUM> and septum <NUM>, allowing the first reagent <NUM> and the second reagent <NUM> to mix into reagent mixture <NUM>. Bottom foil <NUM> holds the mixture in the central chamber until the mixed sample is to be applied to a cassette or test strip. Also visible in these figures is the sampler base <NUM>. The sampler base <NUM> includes the sampler plunger <NUM> and the piercing projection <NUM> for piercing bottom foil <NUM> to release the sample onto a test strip after mixing.

<FIG> show the next steps in the sampling process. In <FIG>, the combined sampler body <NUM> and blood collector <NUM> are sealed together by virtue of their mated fit and may be agitated in order to mix the blood sample in capillary tube <NUM> with the reagent mixture. In <FIG>, the blood sample has been mixed and capillary tube <NUM> is largely empty. The combined blood sample and reagent mixture <NUM> then is ready to be applied to a cassette or test strip by piercing the foil <NUM> according to a different procedure not addressed herein. In this way, the two reagents may be kept separate and combined in a seamless fashion from the point of view of the user. This improves the shelf life of the device by preventing the reagents (buffers) from degrading due to their combination. In some alternatives, additional separation layers may be added. The addition of more separation layers may increase the number of compartments provided in the central chamber. Generally, the additional separation layers or septums should be within the range of the blood sampler body such that they may be pierced during insertion; however, they cannot be placed too high towards the aperture, since this will result in the leaking/pushing out of liquid when the blood sampler body is inserted.

<FIG> show views of the septum <NUM>. Septum <NUM> includes a hinge feature <NUM>, breakaway sections <NUM>, and tearoff sections <NUM>. In some embodiments, breakaway sections are <NUM> (. <NUM> inches) thick and tearoff sections are <NUM> (<NUM> inches) thick. This is purely exemplary. In some embodiments, breakaway sections are one or more times <NUM> (tenths of an inch) thick and tearoff sections are one or more times <NUM> (hundredths of an inch) thick. As above, this is merely an example. The point of this is to provide areas where the septum may rip more easily to provide a more regular breaking pattern. <FIG> shows septum <NUM> in the sampler body. <FIG> shows an alternative embodiment of a septum <NUM>. Septum <NUM> includes panel sections <NUM>, center section <NUM>, connection section <NUM>, and tearaway sections <NUM> that separate the panels, center, and connection. Numerous other geometries will occur to those of ordinary skill in the art based on the teaching of this disclosure.

Claim 1:
A system for mixing a sample with a combined buffer, the system comprising:
a sampler body (<NUM>), the sampler body including a first reservoir and a second reservoir;
a first separator (<NUM>) forming a first chamber with the sampler body for the first reservoir;
a second separator (<NUM>) forming a second chamber with the sampler body for the first reservoir; and
a third separator (<NUM>), in conjunction with the second separator, forming a third chamber and a fourth chamber, respectively, both in conjunction with the sampler body, for the second reservoir;
a blood collector (<NUM>), the blood collector including a first piercing projection (<NUM>), the blood collector shaped to mate with the sampler body (<NUM>), such that when the blood collector is inserted into the sampler body at an aperture in the sampler body, liquid cannot escape from the combination of the sampler body (<NUM>) and the blood collector, wherein upon insertion of the blood collector (<NUM>) into the sampler body (<NUM>), the first piercing projection (<NUM>) of the sampler body pierces the first (<NUM>) and second (<NUM>) separators, and
a sampler base (<NUM>) including a sampler plunger (<NUM>) and a second piercing projection (<NUM>) configured to pierce the third separator (<NUM>) to release the sample onto a test strip after mixing.