Positive displacement pipette tip for motorized control automation or instrument system
A positive displacement pipette tip for motorized control automation or liquid handling instrument system is disclosed. The positive displacement pipette tip includes a pipette tip and a pipette plunger. An interface portion of the pipette tip of the positive displacement pipette tip is designed to be used in combination with a zero-insertion force pipette tip clamping mechanism in, for example, a liquid handling instrument. Further, the pipette plunger of the positive displacement pipette tip is designed to be used in combination with a zero-insertion force pipette plunger clamping mechanism in, for example, a liquid handling instrument.
1. A pipette tip, comprising: a pipette tip having an interface portion and a pipette tip body, the interface portion having an inner wall and a receptacle, the pipette tip body having a fluid channel along the length of the pipette tip body, the fluid channel having an opening at the distal end of the fluid channel; and a pipette plunger positioned along the inside of the pipette tip, the pipette plunger having a plunger upper portion, a plunger centering portion, and a plunger tip having a distal tip portion, wherein the receptacle is adapted to receive the plunger centering portion, and wherein the fluid channel is adapted to receive the distal tip portion of the plunger tip, wherein the plunger upper portion has an outer wall, the outer wall including vertical outer wall features, and wherein the plunger upper portion is configured to be fitted to a mating component of a liquid handling instrument with assistance of the vertical outer wall features.
2. The pipette tip of claim 1 , wherein the fluid channel has a tapered tip at the distal end of the fluid channel.
3. The pipette tip of claim 2 , wherein the distal tip portion of the pipette plunger has a rounded portion adapted to mate with the opening and the tapered tip at the distal end of the fluid channel.
4. The pipette tip of claim 3 , wherein the distal tip portion has tapered sidewalls corresponding to the tapered tip of the fluid channel.
5. The pipette tip of claim 4 , wherein the fluid channel has walls, the distal tip portion having an outer upper edge sized to slideably seal against and along the walls of the fluid channel sufficient to minimize the void between the tapered tip of the fluid channel and the tapered sidewalls of the distal tip portion.
6. The pipette tip of claim 5 , wherein the outer upper edge has a sealing ring feature formed thereon.
7. The pipette tip of claim 1 , wherein the pipette tip is formed of a polymeric material.
8. The pipette tip of claim 7 , wherein the pipette plunger is formed of the polymeric material that is same as the pipette tip.
9. The pipette tip of claim 7 , wherein the pipette plunger is formed of a polymeric material that is different from the polymeric material of the pipette tip.
10. The pipette tip of claim 1 , wherein the inner wall of the interface portion includes vertical inner wall features.
11. The pipette tip of claim 10 , wherein each of the vertical inner wall features is a raised or protruding vertical line formed along the inner wall of the interface portion.
12. The pipette tip of claim 1 , wherein each of the vertical outer wall features is a raised or protruding vertical line formed along the outer wall of the plunger upper portion.
13. The pipette tip of claim 1 , wherein the interface portion has an upper rim with a set of spacer features.
14. A liquid handling system, comprising: a pipette tip having an interface portion and a pipette tip body, the interface portion having an inner wall and a receptacle, the pipette tip body having a fluid channel along the length of the pipette tip body, and the fluid channel having an opening at the distal end of the fluid channel; a pipette plunger positioned along the inside of the pipette tip, the pipette plunger having a plunger upper portion, a plunger centering portion, and a plunger tip having a distal tip portion, wherein the receptacle is adapted to receive the plunger centering portion, wherein the plunger upper portion has an outer wall, the outer wall including vertical outer wall features, and wherein the plunger upper portion is configured to be fitted to a mating component of a liquid handling instrument, and wherein the fluid channel is adapted to receive the distal tip portion of the plunger tip; and a zero-insertion force pipette tip clamping mechanism adapted to manipulate the pipette tip and pipette plunger.
15. The liquid handling system of claim 14 , wherein the zero-insertion force pipette clamping mechanism includes a pipette tip collet and a pipette tip lock mechanism.
16. The liquid handling system of claim 15 , wherein the pipette tip collet includes a pipette tip collet upper ring plate and collet chuck portion for fitting inside the interface portion of the pipette tip.
17. The liquid handling system of claim 16 , wherein the collet chuck portion has a serrated feature adapted to increase the friction to the interface portion of the pipette tip.
18. The liquid handling system of claim 17 , wherein the collet chuck portion is a segmented band or sleeve for fitting inside the interface portion.
19. The liquid handling system of claim 18 , wherein the collet chuck portion is adapted to expand and lock against the inner wall of the interface portion.
20. The liquid handling system of claim 15 , wherein the pipette tip lock mechanism includes a pipette tip lock upper ring plate and a hollow sleeve portion for fitting inside the collet chuck portion.
21. The liquid handling system of claim 20 , wherein the collect chuck portion is adapted to expand against the inside wall of the interface portion when the hollow sleeve portion is fitted inside the collet chuck portion of the pipette tip collect, and
wherein the collet chuck portion is adapted to retract and become loose with respect to the interface portion when the hollow sleeve portion is withdrawn from the collect chuck portion of the pipette tip collet.
22. The liquid handling system of claim 14 , wherein the zero-insertion force pipette clamping mechanism includes a pipette plunger collet and a pipette plunger lock mechanism.
23. The liquid handling system of claim 22 , wherein the pipette plunger collet has a shaft portion and a collet chuck portion for fitting around the plunger upper portion of the pipette plunger.
24. The liquid handling system of claim 23 , wherein the collet chuck portion is a segmented band or sleeve for fitting around the plunger upper portion of the pipette plunger, the collet chuck portion being adapted to expand and lock against the outside wall of the plunger upper portion that is inside the collet chuck portion.
25. The liquid handling system of claim 24 , wherein the pipette plunger lock mechanism includes an upper ring plate and a hollow sleeve portion for fitting around the plunger collet.
26. The liquid handling system of claim 25 , wherein the collet chuck portion is adapted to be closed against the plunger upper portion of the pipette plunger when the hollow sleeve portion is slid around the collet chuck portion of the plunger collect, and
wherein the collect chuck portion is adapted to release the plunger upper portion of the pipette plunger when the hollow sleeve portion is withdrawn from the collect chuck portion of the plunger collet.
27. The liquid handling system of claim 14 , wherein the zero-insertion force pipette clamping mechanism includes a pair of pipette plunger clamping mechanisms, a pair pipette plunger collets, a fixed upper plate, a lower plate, and two springs between the upper plate and the lower plate,
wherein the upper ends of the pipette plunger collets are held fixed to the upper plate,
wherein the lower plate and two springs are movable with respect to the upper plate, and
wherein each spring is adapted to provide spring force to a corresponding pipette plunger lock mechanism that passes in slidable fashion through the lower plate, the pipette plunger lock mechanisms are moveable with respect to the plunger collets.