FIELD OF THE INVENTION

[0001] Embodiments of the present disclosure relate to devices and methods of using the same that enable improved pipetting.

DESCRIPTION OF THE RELATED ART

[0002] Laboratory techniques such as cell culture, enable the study of biological systems with efficiency and yield useful results for a variety of applications including for example describing infectivity and assessing drug susceptibility. The processing of samples for such systems often requires the extraction and removal of precise quantities of liquids, chemicals, supernatants and the like from samples, and frequently the process is subject to inaccuracy resulting in inconsistency and sometimes unreliable results.

[0003] What is needed is the ability to specifically, accurately and consistently process samples in order to characterize and analyze particles, such as biological cells, in a way that provides meaningful and reliable information for a range of applications. In particular, with regarding to techniques such as cell culture, what is needed are devices that enable the ability to pipette exact and consistent quantities of liquid from cell/particle containing vessels such as multi-well plates, test-tubes and the like. Ideally, such devices should be customizable, re-usable or disposable, and easy to use with existing laboratory equipment.

SUMMARY OF THE INVENTION

[0004] Embodiments of the present disclosure relate to novel pipette tip guides and methods of using the same for optimizing the process of pipetting.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Fig. 1 provides a schematic of a reusable or disposable pipette tip guide. In this schematic a representative cover for a 96 well plate is provided, however such a cover may be customized for any other well plate or configuration (including for example a plate comprising 24, 48, 192, 288, 384, etc. wells). The cover comprises openings/holes of a specific or predetermined diameter that prevent the tip of a specific pipette from disturbing a cell pellet at the bottom of the well plate. The hole size can be adjusted and customized in order to accommodate a specific tip, sample height, and well plate dimension. A multichannel pipettor can be used with pipette tips shown as they enter the well plate through the pipette guide, which prevents the tip from getting too close to the bottom, disturbing or accidentally removing a cell pellet. The shape of the guide is such that it attaches to the plate in a specific way to align each pipette tip in a precise position within each well in one or more dimensions. Figure 1 provides a side view of the cover on a well plate, a proximal top view of the cover on a well plate and a view of the cover separate from the well.

[0006] Figure 2 provides a schematic demonstrating an alternate configuration or embodiment of a pipette tip guide as envisioned herein. In an embodiment, the pipette tip guide may be reusable or disposable. As shown in Figure 2, a pipette tip guide constructed of plastic or other material, may be press fit onto the pipette tips attached to a multichannel pipettor. The opening of a given diameters serve to stop the pipette from contacting the bottom of the well or keeping it a specific distance from the bottom to preserve the cell pellet. The diameter is a function of the pipette, the well plate depth and the application requirements (cell pellet size, density, etc.).

[0007] Figure 3 provides an embodiment depicting a disposable pipette tip guide packaging. A box to hold the plastic pipette guides and facilitate pickup and seating on the pipette tips attached to the multichannel pipettor is shown. The box design has a shelf and recessed compartments to accommodate the tips while holding the guide for press fit attachment to the pipette tips. After use the pipette guides are disposed of automatically with the pipette tips.

[0008] Figure 4 provides a schematic demonstrating an alignment jig and tip size selector. An alignment jig is provided to test and enable the selection of the hole diameters desired for a given pipette tip for a particular depth in an vial or well in a specific applications. The alignment jig and hole selector allows the rapid selection of pipette guide selection (hole diameter) for the desired features of a new pipette tip, brand or style. The separation between the upper and lower pieces of the jig can be customized for a particular well plate style or dimension. Plate types may include standard, deep-well, round, and flat bottom.

[0009] Figure 5 provides a schematic demonstrating an individual pipette tip guide. In this embodiment, the tip guide provided is intended for a single pipette versus previously described designs for a multichannel pipettor, which would be used with multiple pipettes. Figure 5 further demonstrates the general concept of how the guide is envisioned to operate: submerging the tip and guide into a well containing a cell pellet and some medium above, removing the precise amount of medium dictated by the height of the well, size of the pipette tip, and size of the hole in the tip guide, leaving the pellet undisturbed and ready for further processing or analysis.

[0010] Figure 6 provides a schematic demonstrating one embodiment wherein the pipette guide is integrated with the pipette itself. As shown, the pipette tip with integrated guide is built into the body of the pipette. Must be used with a specific well plate to ensure proper function.

[0011] Figure 7 provides a schematic showing one embodiment of a sample harvest workflow. The figure summarizes steps describing the use of the system and how it could be adapted to multiplex the harvesting procedure for cell -based assays. Cells grown in any format, including but not limited to flasks, well plates, and bioreactors, could be harvested and then transferred into a larger format (96 or greater). Cells would then be pelleted, generally using centrifugation, to concentrate the cells in a pellet at the bottom of the well. The pipette tip guide would then be used in combination with a multichannel pipette to remove the precise amount of liquid required, leaving a pellet at the bottom of the well with a minimal amount of medium. At this point, cells are ready for further processing. This could include, but is not limited to: (1) resuspension of the cells in order to change concentration (using the same fluid) or sample matrix (using a different fluid) for direct analysis or transfer to another plate; (2) resuspension of the cells to facilitate further cellbased processing steps, including antibody labeling, and/or (3) cell lysis in order to perform molecular assays for detection of nucleic acids or proteins as an example. In addition, the pipette guide may be used for robotic systems in order to easily calibrate the motion systems to an exact height based on the desired volume remaining in the well. [0012] Figure 8 provides an embodiment of the pipette tip guides envisioned herein wherein the guide is attached to a well plate, such as a 96 well plate in an manner in which it can be moved along the well. In the embodiment depicted, the guide may comprise a feature wherein it is attached (or snapped) to a well plate and slides along grooves etched on a side of the well plate. In certain embodiments, the guide may be colored coded in order to depict a particular hole or diameter size.

[0013] Figure 9 provides an embodiment demonstrating a possible use of the pipette guide tips with automated calibrating systems.

DETAILED DESCRIPTION

[0014] The present invention is described with reference to particular embodiments having various features. It will be apparent to those skilled in the art that various modifications and variations can be made in the practice of the present invention without departing from the scope or spirit of the invention. One skilled in the art will recognize that these features may be used singularly or in any combination based on the requirements and specifications of a given application or design. One skilled in the art will recognize that the systems and devices of embodiments of the invention can be used with any of the methods of the invention and that any methods of the invention can be performed using any of the systems and devices of the invention. Embodiments comprising various features may also consist of or consist essentially of those various features. Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention. The description of the invention provided is merely exemplary in nature and, thus, variations that do not depart from the essence of the invention are intended to be within the scope of the invention.

[0015] Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting.

[0016] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as would be commonly understood or used by one of ordinary skill in the art encompassed by this technology and methodologies.

[0017] Texts and references mentioned herein are incorporated in their entirety, including United States Provisional Application Serial No. 63/141,142 filed on January 25, 2021.

[0018] In an embodiment, the invention comprises novel pipette tip guides and methods of using the same for optimizing the process of pipetting. The unique pipette tip guides of the invention enable a variety of advantages including, but not limited to, improved accuracy with regard to tip positioning, a reduction in unwanted aspiration of cell pellets, and improved control of the volume of fluid above a cell pellet.

[0019] In laboratory processes such as cell culture, particles such as cells are grown in controlled environments under carefully controlled conditions. In the process of culturing and implementing such techniques, the cells undergo frequent cycles of washing and/or resuspension in different fluids. The cells are separated from the fluid they were surrounded in using a centrifuge to deposit them at the bottom of a well in a plate or a vial making a small pellet at the bottom. The fluid or supernatant is removed using a pipette and then replaced to wash or change the fluids with media or reagents. If the user is not careful, the pipette can come to close to the pellet of cells and accidentally aspirate some or all of the pellet. The smaller the vial or well, the more difficult it becomes to do this accurately. If sufficient fluid is not removed, then the exchange of fluids may not be complete affecting the biological assay or process. This process is often performed using individual tubes rather than multi-well plates, because it is difficult to simultaneously guide a pipette at a precise height above the pellet in order to avoid disturbing it. However, the tubes are cumbersome and laborious to handle, especially for large numbers of samples. This increases labor and also potentially decreases quality and consistency, because each manipulation is distinct and by increasing the amount of processing time required for the cells, the potential for cellular change is also increased. [0020] Provided herein are novel guides for pipette tips that enable improved pipetting including improved accuracy and consistency in implementing cell culture processing. The guides as envisioned herein may be constructed of plastic, polymer, glass, fused silica, metal, composite or any other suitable material. The guides may be customized according to the intended use: including for example, vessel with which they are being used, or the environment in which they are being used. The guides may be single use (disposable), or re-usable. Re-usable embodiments may be constructed of materials that enable the guide to be sterilized. The guides may be color-coded to signify particular features such as diameter, hole size, plate size, pipette compatibility and the like.

[0021] As shown in Figure 1, a reusable or disposable pipette tip guide may be configured for a 96 well plate, however it may also be customized for any other well plate or configuration (including for example a plate comprising 24, 48, 192, 288, 384, etc. wells). The guide functions as a “cover” that comprises openings/holes of a specific or predetermined diameter that prevent the tip of a specific pipette from descending too deep and consequently disturbing a cell pellet at the bottom of the well plate. The hole size can be adjusted and customized in order to accommodate a specific tip, sample height, and well plate dimension.

[0022] As shown in Figure 4, an accessory to the pipette tip guides comprises an alignment jig and tip size selector. This accessory enables the selection of the hole diameters desired for a given pipette tip for a particular depth in an vial or well in a specific applications.

[0023] In certain embodiments, the novel pipette tip guides of the invention may be utilized with devices for automated sample analysis, wherein the samples are present in vials, vessels, wells, multi-well plates and the like. The samples may consist of various particles, cells, biological and/or chemical entities. The pipette tip guides enable accurate aspiration of particulate samples for use in fluidic based instruments or systems for analysis. Suitable fluidic based instruments for analysis may utilize Laser Force Cytology (LFC), or other means.

[0024] In an embodiment, the novel pipette tip guides of the invention may be utilized with a variety of samples wherein the samples include, but are not limited to, biological cells, plant cells (algal cells or others), prokaryotic cells (bacteria), eukaryotic cells, yeast, fungus, mold cells, red blood cells, neurons, egg cell (ovum), spermatozoa, white blood cells, basophils, neutrophils, eosinophils, monocytes, lymphocytes, macrophages, platelets, vesicles, exosomes, stromal cells, multicellular constructs such as spheroids, mesenchymal cells, and induced pluripotent stem cells (iPSCs), cancer cell lines, primary cancer cells, T cells, B cells, monocytes, macrophages, other white blood cells, red blood cells, genetically engineered T cells or any other engineered cell or gene therapy modified product as well as subcellular components including nuclei, mitochondria, or chloroplasts. The samples may be synthetically manufactured or obtained from natural sources. The samples may be obtained from bodily fluids or bodily matter, including but not limited to, tears, saliva, sputum, blood, plasma, lymph, urine, sweat, pus, nasal discharge or semen.