Patent Application
20210247411
The disclosure is directed to fluid droplet dispense devices that are used to accurately dispense one or more fluids onto or into precise areas of a substrate or for building up layers of material in predetermined areas on the substrate and to maintenance methods and apparatus for the fluid droplet dispense devices.
In the medical field, in particular, there is a need for automated sample preparation and analysis. The analysis may be colorimetric analysis or require the staining of samples to better observe the samples under a microscope. Such analysis may include drug sample analysis, blood sample analysis and the like. In the analysis of blood, for example, blood is analyzed to provide a number of different factors that are used to determine the health of an individual. When there are a large number of patients that require blood sample analysis, the procedures may be extremely time consuming. Also, there is a need for accurate preparation of the samples so that the results can be relied on. There are many other situations that require sample analysis in the medical field and in other fields that can benefit from the use of analytical instruments that provide accurate and reproduceable results, such as micro-titration of multiple samples.
Mirco-well plates, slides and other substrates are used for many experiments and laboratory procedures. The process of filling the wells in a micro-well plate or spotting is often performed manually or using expensive lab equipment. In some cases, the wells are filled with hand operated pipettes. In other cases, high-end automated devices based on pipette technology are used to fill the well plates. Such automated devices accommodate a dispense head that moves across a substrate to deposit fluid.
Precise deposition of fluid into the wells of a micro-well plate requires all nozzles of the ejection heads of the fluid droplet cartridges to be in pristine condition. In order to maintain the nozzles of the ejection head in pristine condition, a maintenance station is provided in the digital dispense device whereby all the nozzles of the ejection head are fired at regular intervals to maintain the pristine condition of the nozzles. Maintenance of the nozzles is required to prevent build-up of contaminants within the nozzles that may cause clogging or misfiring of the nozzles. Conventional printing devices typically use permanently installed maintenance stations. However, when using a fluid droplet dispense device for applications in which the fluids dispensed can vary to a much greater degree, the problem arises that some of the fluids may be incompatible with each other, and a permanent maintenance spit station is not a viable, safe solution for such applications. In addition, in some experiments, the remainder of the fluids in the ejection head will need to be disposed of safely and in an approved manner. For example, some fluids may be characterized as biohazard waste materials.
Another problem associated with conventional, permanently installed maintenance stations is that a fine mist is often created as the ejection head dispenses fluid at the maintenance station.
In applications wherein the digital dispense device is used to for life sciences procedures, some of the fluids that are dispensed may include drugs, living cells, proteins, enzymes, antibodies and many other types of fluids that must be disposed of because of biohazards and other concerns. For some applications, mixing of different fluids the permanent maintenance station 18 may be undesirable or hazardous. Conventional digital dispense devices 10 that include a permanent maintenance station do not accommodate removal of the waste fluids from the digital dispense device. Accordingly, there is a need for an improved maintenance apparatus for a fluid droplet dispense device to prevent contamination of the device components and to dispose of hazardous or biowaste fluids that may be dispensed by the device during maintenance of the ejection head cartridge 12.
In view of the foregoing, an embodiment of the disclosure provides a maintenance reservoir for a digital dispense system. The maintenance reservoir includes an elongate trough disposed in a micro-well plate holder for holding fluid dispensed from a fluid droplet ejection head of a fluid droplet cartridge in the digital dispense system. The maintenance reservoir is disposed in the micro-well plate holder on at least one side of a micro-well plate and includes a position indicator to signify if the elongate trough is present or absent from the micro-well plate holder.
In another embodiment there is provided a digital dispense system for ejection of fluids onto a substrate. The digital dispense system includes a housing unit and a fluid droplet ejection cartridge disposed in the housing unit. The fluid droplet ejection cartridge contains one or more fluids and is disposed on a fluid cartridge translation mechanism for moving the fluid droplet ejection cartridge back and forth in an x-direction within the housing unit. A micro-well plate holder is provided for holding a micro-well plate below the fluid droplet ejection cartridge. A removable maintenance reservoir is disposed in the micro-well plate holder for periodic maintenance of the fluid droplet ejection cartridge.
In yet another embodiment there is provided a method for maintaining a fluid droplet ejection cartridge in a digital fluid dispense system. The method includes providing a housing unit and a fluid droplet ejection cartridge disposed in the housing unit, the fluid droplet ejection cartridge containing one or more fluids and being disposed on a fluid cartridge translation mechanism for moving the fluid droplet ejection cartridge back and forth in an x-direction within the housing unit. A micro-well plate holder is provided for holding a micro-well plate below the fluid droplet ejection cartridge during fluid dispensing of the one or more fluids into wells of the micro-well plate. A maintenance reservoir that includes an elongate trough is disposed on at least one side of the micro-well plate holder. The elongate trough includes a position indicator to signify if the elongate trough is present or absent from the micro-well plate holder. The fluid droplet ejection cartridge is periodically moved to a position adjacent to the elongate trough, and fluid is ejected from the fluid droplet ejection cartridge into the elongate trough for a predetermined period of time.
In some embodiments, the elongate trough is removable from the micro-well plate holder. In some embodiments, the elongate trough has a length that corresponds to a length of a column of wells in the micro-well plate. In still other embodiments, the elongate trough has a volume that is equal to a volume of fluid in a fluid droplet ejection cartridge. In some embodiments, the elongate trough has a rectangular cross-sectional shape.
In some embodiments, the elongate trough also includes a position indicator that is used to signify if the elongate trough is present or absent from the micro-well plate holder. In other embodiments, fluid ejection from the fluid droplet ejection cartridge is terminated when a sensor fails to detect the position indicator.
In some embodiments, fluid is ejected from the fluid droplet ejection cartridge into the elongate trough for a period of time sufficient to clean nozzles on the fluid droplet ejection cartridge. In other embodiments, fluid is ejected from the fluid droplet ejection cartridge into the elongate trough for a period of time sufficient empty fluid from the fluid droplet ejection cartridge.
An advantage of the disclosed embodiments is that it provides unique low-cost maintenance reservoir that can be removed from the digital dispense system so that fluid ejected from the fluid droplet ejection cartridges can be disposed of in an environmentally safe manner. Other features and advantages of the disclosed embodiments may be evident by reference to the attached drawings and following disclosure.
With reference to
The micro-well plate 40 used with the digital dispense device 10 is illustrated in
An important feature of the improved micro-well plate holder 50 and trough 52 is that there is a position indicator 54 at one end of the trough 52 that enables a sensor in the digital dispense device to determine if the trough 52 is present on the well-plate holder 50. In some embodiments, the position indicator is a raised area 54 or flat area of the trough 52 that can be sensed by a sensor in the digital dispense device. The sensor may be a lever that is raised when the micro-well plate holder 50 contains the trough 52 and the raised area 54 and that is lowered or falls when a micro-well plate holder does not contain the trough 52. In another embodiment, the sensor may be an optical sensor that is used to detect indicia that indicates the presence or absence of the trough 52. Any other suitable sensor, known to those skilled in the art may be used. The sensor may be configured by software in the digital dispense device to alert the user that the trough 52 is not present. The sensor may also be configured to alert a user that the micro-well plate holder 52 and micro-well plate have been removed from the device once the wells 42 have been filled, and the device is ready for a new micro-well plate 40 and new fluid deposition procedure.
In another embodiment illustrated in
In another embodiment, the trough 52 may be included in an x-y table that is designed to hold and move the micro-well plate 40 for filling the wells 42 rather than using a well plate holder as described above. In the embodiments described herein, the trough and well plate holder may be made of a variety of materials including metals, plastics and ceramics. The materials for trough and well plate holder are desirably selected from materials that are compatible with the fluids being ejected from the fluid droplet ejection cartridges.
It is noted that, as used in this specification and the appended claims, the singular forms “a,” “an,” and “the,” include plural referents unless expressly and unequivocally limited to one referent. As used herein, the term “include” and its grammatical variants are intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other like items that can be substituted or added to the listed items
For the purposes of this specification and appended claims, unless otherwise indicated, all numbers expressing quantities, percentages or proportions, and other numerical values used in the specification and claims, are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.
While particular embodiments have been described, alternatives, modifications, variations, improvements, and substantial equivalents that are or can be presently unforeseen can arise to applicants or others skilled in the art. Accordingly, the appended claims as filed and as they can be amended are intended to embrace all such alternatives, modifications variations, improvements, and substantial equivalents.
