WELL SEALS IN PIPETTE WORKSTATIONS
A pipette workstation of the type dispensing fluids into a microtiter plate with well closure structures that are thimble-shaped members with ridges that form a seal. The closure structures have a beveled nose lower end for self-centering entry into a well with a lower peripheral ridge acting as a first seal. An intermediate peripheral ridge contacts the wall of the well and forms a second seal barrier. An upper peripheral ridge has a diameter that barely enters the well for wedge action stoppage of entry of closure member into the well and further sealing the well. A pipette head with a nozzle array attaches to an array of seals and inserts the seals into wells. The pipette head uses a vacuum force to remove the seals.
1 . In a pipette workstation of the type having a pipette loading reagents or samples into a microtiter plate, the improvement comprising:
a well closure structure comprising a thimble-shaped ridged structure with a closed downhole nose end smaller than a well diameter with a lower peripheral ridge that contacts walls of the well and an upper peripheral ridge having a diameter having a wedge fit into the well beyond a small diameter, the structure having a closed bottom and a open top, with the open top sized to accommodate a pipette nozzle.
2 . The apparatus of claim 1 further comprising an intermediate ridge spaced from the lower and upper ridges and having a ridge diameter less than the upper ridge and not less than the lower ridge.
3 . The apparatus of claim 1 wherein the downhole nose of the lower ridge is beveled.
4 . The apparatus of claim 1 wherein the pipette workstation comprises a multi-channel pipette.
5 . The apparatus of claim 1 wherein the pipette workstation comprises an 8-channel pipette.
6 . The apparatus of claim 1 wherein the microtiter plate is a multi-well plate.
7 . The apparatus of claim 1 wherein the microtiter plate is a 96-well plate.
8 . The apparatus of claim 1 wherein each well closure structure is made of a yieldable material.
9 . The apparatus of claim 1 wherein each well closure structure is made of rubber.
10 . The apparatus of claim 1 wherein each well closure structure is made of a deformable polymer.
11 . The apparatus of claim 1 further comprising a plurality of well closure structures connected along a continuous strip.
12 . A method for sealing one or more wells of a well plate, comprising:
moving a pipette head having a nozzle array to a well seal array storage location, each well seal comprising a well closure structure comprising a thimble-shaped ridged structure with a closed downhole nose end smaller than a well diameter with a lower peripheral ridge that contacts walls of the well and an upper peripheral ridge having a diameter having a wedge fit into the well beyond a small diameter, the structure having a closed bottom and a open top, with the open top accommodating a pipette tip;
inserting each pipette nozzle into the open top of a well seal and attaching the well seal to the pipette nozzle;
moving the nozzle array with the attached well seals into wells of a microtiter plate; and
ejecting the well seals from the nozzle array, the upper peripheral ridge of each seal preventing the well seal from being pushed too far in the well.
13 . The method of claim 12 further comprising moving the nozzle array to the sealed wells and using a vacuum force from the pipette head to remove the seals.