Acoustically mediated fluid transfer methods and uses thereof

Abstract

Invention methods employ the use of acoustic waves to transfer small amounts of fluid in a non-contact manner. In invention methods, acoustic waves are propagated through a separated pool of a source fluid in such a manner that causes the ejection of a single micro-droplet from the surface of the pool. The droplet is ejected towards a target with sufficient force to provide for contact of the droplet with the target. Because the fluid is not contacted by any fluid transfer device such as a pipette, the opportunities for contamination are minimized. Invention methods may be employed to transfer fluids from an array of source sites to an array of target sites, thereby enabling the precision automation of a wide variety of procedures including screening, and synthesis procedures commonly used in biotechnology.

1 - 57 . (canceled) 
     
     
         58 . A method of forming an array of compound sites for identifying properties of chemical or biological compounds, the method comprising
 (a) ejecting a liquid from a well using focused acoustic energy,   (b) depositing the ejected liquid at a location on a substrate,   (c) ejecting a subsequent liquid from a subsequent well using focused acoustic energy,   (d) depositing the ejected subsequent liquid at a subsequent location on the substrate, and   (e) repeating steps (c) and (d) to form the array.   
     
     
         59 . A method according to  claim 58  wherein said liquid and said subsequent liquid comprise oligonucleotides. 
     
     
         60 . A method according to  claim 58  wherein said liquid and said subsequent liquid comprise polynucleotides. 
     
     
         61 . A method according to  claim 58  wherein said liquid and said subsequent liquid comprise cells. 
     
     
         62 . A method according to  claim 58  wherein said liquid and said subsequent liquid comprise proteins. 
     
     
         63 . A method according to  claim 58  wherein said liquid and said subsequent liquid comprise chemical compounds. 
     
     
         64 . A method according to  claim 58  wherein said liquid has a surface, and a distance between an acoustic liquid deposition emitter that produces the focused acoustic energy and said surface is adjusted in response to the liquid being ejected from the well. 
     
     
         65 . A method according to  claim 58  wherein said well and said subsequent well form a portion of a multiwell plate. 
     
     
         66 . A non-contact method for transferring small amounts of source fluid, said method comprising propagating an acoustic wave from an acoustic liquid deposition emitter through a removable source fluid containment structure into a pool of a source fluid, wherein:
 a) said acoustic liquid deposition emitter is in contact with said source fluid containment structure through a liquid interposed between said acoustic liquid deposition emitter and a first surface of said source fluid containment structure, said liquid transmitting the acoustic wave from the acoustic liquid deposition emitter to the source fluid containment structure,   b) said pool of source fluid is one of a plurality of pools of source fluid on a second surface of said source fluid containment structure that is opposite said acoustic liquid deposition emitter; and   c) said acoustic wave ejects at least one droplet of said source fluid from said pool.   
     
     
         67 . A method according to  claim 66 , wherein said at least one droplet contacts a target after being ejected from the surface of said source fluid. 
     
     
         68 . A method according to  claim 66 , wherein said acoustic liquid deposition emitter comprises a piezoelectric transducer for generation of said acoustic wave. 
     
     
         69 . A method according to  claim 68 , wherein said piezoelectric transducer is mechanically coupled to an acoustic wave channel structure, wherein said acoustic wave channel structure has an acoustic impedance that is greater than the acoustic impedance of said source fluid. 
     
     
         70 . A method according to  claim 68 , wherein said acoustic liquid deposition emitter further comprises a lens for focusing said acoustic wave. 
     
     
         71 . A method according to  claim 70 , wherein said lens is spherical. 
     
     
         72 . A method according to  claim 70 , wherein said lens has an f-value in the range of about 1 to about 4. 
     
     
         73 . A method according to  claim 66 , wherein said at least one droplet has a defined diameter. 
     
     
         74 . A method according to  claim 73 , wherein said defined diameter is in the range of about 1 micrometer to about 1000 micrometers. 
     
     
         75 . A method according to  claim 73 , wherein said defined diameter is controlled by varying one or more of frequency, voltage, and duration of an energy source used to excite a piezoelectric transducer and thereby propagate said acoustic wave. 
     
     
         76 . A method according to  claim 66 , wherein said pool of source fluid is contained within a well having a bottom, sides and an open top for the ejection of said droplet there through. 
     
     
         77 . A method according to  claim 66 , wherein said source fluid containment structure comprises one or more regions of hydrophilicity for containing said plurality of pools of source fluid. 
     
     
         78 . A method according to  claim 67 , wherein said plurality of pools of source fluid is arranged as an array and wherein said target comprises an array of target zones for receiving said droplet. 
     
     
         79 . A method according to  claim 78 , wherein each pool of source fluid in the array comprises a different source fluid. 
     
     
         80 . A method according to  claim 78 , wherein said array of pools of source fluids is contained in an array of source wells, wherein each of said wells comprises a bottom, sides and an open top for the ejection of said droplet there through. 
     
     
         81 . A method according to  claim 78 , wherein a target zone of said array of target zones is positioned opposite a selected source fluid, such that liquid ejected from the selected source fluid contacts said target zone. 
     
     
         82 . A method according to  claim 80 , wherein said method further comprises positioning of said acoustic liquid deposition emitter relative to said array of source wells to provide for user-defined association of said acoustic liquid deposition emitter with a selected source fluid for ejection of at least one droplet therefrom. 
     
     
         83 . A method according to  claim 82 , wherein said positioning is accomplished by computer-controlled translation of said liquid deposition emitter with respect to said array of source wells. 
     
     
         84 . A method according to  claim 82 , wherein said positioning is accomplished by computer-controlled translation of said array of source wells with respect to said liquid deposition emitter. 
     
     
         85 . A method according to  claim 66 , wherein said pool of source fluid comprises one or more source materials. 
     
     
         86 . A method according to  claim 85 , wherein said one or more source materials comprise one or more biological or chemical compounds. 
     
     
         87 . A method according to  claim 86 , wherein said one or more source materials bear a detectable label. 
     
     
         88 . A method according to  claim 87 , wherein said detectable label is fluorescent or radioactive. 
     
     
         89 . A method according to  claim 86 , wherein said one or more biological compounds comprise a nucleic acid, a polypeptide, a eukaryotic cell, a prokaryotic cell, or a combination thereof. 
     
     
         90 . A method according to  claim 89 , wherein said nucleic acid is DNA or RNA. 
     
     
         91 . A method according to  claim 86 , wherein said one or more source materials comprise a mono- or oligonucleotide, or combination thereof. 
     
     
         92 . A method according to  claim 85 , wherein:
 said at least one droplet contacts a target after being ejected from the surface of said source fluid; and   said target is functional for binding said one or more source materials.   
     
     
         93 . A method according to  claim 92 , wherein said target bears one or more target materials. 
     
     
         94 . A method according to  claim 93 , wherein said one or more target materials comprise one or more biological or chemical compounds. 
     
     
         95 . A method according to  claim 94 , wherein said one or more biological compounds comprise a nucleic acid, a polypeptide, or a combination thereof. 
     
     
         96 . A method according to  claim 95 , wherein said nucleic acid comprises s DNA or RNA. 
     
     
         97 . A method according to  claim 67 , wherein said target comprises a biological or chemical compound. 
     
     
         98 . A method according to  claim 66 , further comprising detecting the volume or level of source fluid present in said fluid containment structure. 
     
     
         99 . A method according to  claim 98 , wherein said detecting is performed by directing an acoustic wave at said source fluid, receiving a reflection of said acoustic wave, and determining the level of said source fluid based on the characteristics of said reflected acoustic wave. 
     
     
         100 . A method according to  claim 98 , wherein said volume or level is performed by an acoustical detector coupled to a computer, and wherein said computer computes a change in volume or level based on a first signal received from the detector before said ejecting of said droplet, and a second signal received from the detector after said ejecting of said droplet. 
     
     
         101 . A non-contact method for transferring small amounts of a source fluid to a separate target structure, said method comprising activating a piezoelectric transducer thereby propagating an acoustic wave through a liquid which is interposed between said piezoelectric transducer and a first surface of a removable source fluid containment structure, wherein:
 a) said source fluid is contained as a pool on a second surface of said source fluid containment structure that is opposite said piezoelectric transducer, said pool of source fluid one of a plurality of pools of source fluid on said second surface, and   b) said target is positioned to receive a portion of said source fluid ejected from said pool of source fluid as a result of propagation of said acoustic wave through said source fluid.   
     
     
         102 . A method for transferring small amounts of a source fluid from a pool selected from one of a plurality of pools of source fluid located on a first surface of a removable source fluid containment structure, to a separate target structure without physically contacting said source fluid, said method comprising propagating an acoustic wave through said source fluid such that a single droplet of fluid is ejected from the surface of said pool with sufficient energy to bring said droplet into contact with said target, wherein:
 a) said acoustic wave is propagated from a piezoelectric transducer,   b) said piezoelectric transducer is in contact with said source fluid containment structure via a liquid interposed between said piezoelectric transducer and a second surface of said source fluid containment structure,   c) said second surface of said source fluid containment structure is opposite said pool, and   d) said target is opposite said surface of said pool.   
     
     
         103 . A system for performing non-contact transfer of small amounts of source fluid, comprising:
 a source fluid containment structure;   a movable stage, configured to support the source fluid containment structure;   an acoustic liquid deposition emitter in operative contact with the source fluid containment structure;   a liquid interposed between the deposition emitter and the source fluid containment structure;   a fluid level detector for detecting a level or volume of fluid in a source fluid containment structure;   a lens in operative association with the acoustic liquid deposition emitter for focusing an acoustic wave; and   a computer in operable communication with the acoustic liquid deposition emitter for varying one or more of frequency of the acoustic wave; voltage of an energy source used to excite the acoustic liquid deposition emitter; duration of an energy source used to excite the acoustic liquid deposition emitter, or location of the stage relative to the acoustic deposition emitter; and wherein the computer comprises a computer implemented algorithm for adjusting one or more of:   frequency of the acoustic wave; voltage of an energy source used to excite the acoustic liquid deposition emitter; duration of an energy source used to excite the acoustic liquid deposition emitter; or location of the stage relative to the acoustic deposition emitter in response to a change in fluid level or volume detected by the fluid level detector.