Liquid transfer system

Abstract

Aspects of the invention relate to liquid transfer systems including a pipette tip having a body defining an inner volume and having first and second ends, the first end arranged to transfer a volume of liquid into and out of the pipette tip and the second end arranged for attachment to a pipette, and a bladder sealingly attached to the body. In some embodiments, the bladder is disposable in the inner volume. The bladder may be defined by a membranous sac and/or a planar membrane. The bladder may be moveable in response to an applied pressure to transfer liquid. The bladder also may be stretchable to accommodate a volume of fluid. In some embodiments, the pipette tip is used in a cell culture incubator, with a manipulator including a pipette that is in fluid communication with the pipette tip.

1 . A pipette tip comprising:
 a body defining an inner volume and having first and second ends, the first end arranged to pass a liquid into and out of the pipette tip and the second end arranged for attachment to a pipette;   a bladder sealingly attached to the body, wherein the bladder includes a membranous sac in a collapsed configuration disposed in the inner volume; and   
       a pipette shell within the body of the pipette and receptive of the bladder in response to an applied pressure, wherein the pipette shell includes a pipette shell body into which the bladder is configured to be retracted in response to the applied pressure, and wherein the pipette shell is made of a rigid material. 
     
     
         2 . The pipette tip of  claim 1 , wherein the bladder is disposable in the inner volume of the body. 
     
     
         3 . The pipette tip of  claim 1 , wherein the bladder is arranged to cause a volume of liquid to be drawn into or expelled from the inner volume though the first end in response to a pressure gradient applied across the bladder. 
     
     
         4 . The pipette tip of  claim 1 , wherein the bladder is arranged to permit a volume of liquid to be drawn into the inner volume through the first end in response to a negative pressure gradient directed from the first end toward the second end and across the bladder, and wherein the bladder is arranged to permit a volume of liquid to be expelled from the inner volume through the first end in response to a positive pressure gradient directed from the first end toward the second end and across the bladder. 
     
     
         5 . The pipette tip of  claim 4 , wherein the bladder has a first side and a second side, wherein the first side faces the first end of the body, and wherein the negative pressure gradient is generated by drawing a vacuum on the second side. 
     
     
         6 . The pipette tip of  claim 1 , wherein the bladder is attached to the body at one of the first and second ends of the body. 
     
     
         7 . The pipette tip of  claim 1 , wherein the bladder is attached to the body at a location between the first and second ends of the body. 
     
     
         8 . (canceled) 
     
     
         9 . The pipette tip of  claim 1 , wherein the pipette shell is removably attachable to the pipette tip. 
     
     
         10 . The pipette tip of  claim 1 , wherein the bladder is expandable to be at least partially disposed outside of the inner volume. 
     
     
         11 . The pipette tip of  claim 1 , wherein the pipette shell has a volume at least equal to a volume of the bladder. 
     
     
         12 . The pipette tip of  claim 1 , wherein the bladder provides a seal between a first compartment defined between a first side of the bladder and the first end of the body and a second compartment defined between a second side of the bladder and the pipette. 
     
     
         13 . The pipette tip of  claim 12 , wherein the bladder provides a seal while liquid is drawn into the first compartment. 
     
     
         14 . The pipette tip of  claim 1 , wherein the sac is permanently attached to the body at a periphery thereof. 
     
     
         15 . The pipette tip of  claim 1 , in combination with a second pipette tip, the second pipette tip comprising:
 a second body defining a second inner volume and having third and fourth ends, the third end arranged to pass a liquid into and out of the second pipette tip and the fourth end arranged for attachment to a pipette; and   a second bladder sealingly attached to the second body;   wherein the first and second pipette tips are nestable.   
     
     
         16 . The combination of  claim 15 , wherein the second bladder is disposable in the second inner volume. 
     
     
         17 . The combination of  claim 15 , wherein the first pipette tip is nested on top of the second pipette tip. 
     
     
         18 . The combination of  claim 17 , wherein the second bladder is adjacent to the body of the first pipette tip when the first pipette tip is nested on top of the second pipette tip. 
     
     
         19 - 21 . (canceled) 
     
     
         22 . The pipette tip of  claim 1 , wherein, in response to a first applied pressure, the bladder is arranged to move in a direction away from the first end of the body to draw a volume of liquid into the pipette tip. 
     
     
         23 . The pipette tip of  claim 22 , wherein, in response to a second applied pressure, the bladder is arranged to move in a direction toward the first end of the body to transfer a volume of liquid out of the pipette tip. 
     
     
         24 . The pipette tip of  claim 22 , wherein, in response to the first applied pressure, at least a portion of the bladder is arranged to accommodate a volume of liquid. 
     
     
         25 . The liquid transfer device of  claim 22 , wherein the volume of liquid drawn into the pipette tip is proportional to an amplitude of the first applied pressure. 
     
     
         26 - 33 . (canceled) 
     
     
         34 . A pipette tip comprising:
 a body defining an inner volume and having first and second ends, the first end arranged to pass a liquid into and out of the pipette tip and the second end arranged for attachment to a pipette;   a bladder sealingly attached to the body, wherein the bladder includes a membranous sac in a collapsed configuration disposed in the inner volume and wherein the bladder and at least a portion of the inner volume are arranged to accommodate a volume of liquid; and   a pipette shell within the body of the pipette and receptive of the bladder in response to an applied pressure, wherein the pipette shell includes a pipette shell body into which the bladder is configured to be retracted in response to the applied pressure, and wherein the pipette shell is made of a rigid material.   
     
     
         35 - 72 . (canceled)