Pipetting device, pipette tip coupler, and pipette tip: devices and methods

1 . A pipette tip comprising:

a circumscribing sidewall with an open interior passage including an interior surface extending along a central longitudinal axis of the pipette tip between an open proximal end and an open distal end of the pipette tip;

a first section formed in the interior surface of the circumscribing sidewall distal to the open proximal end, the first section comprising:

a cylindrical upper first portion having a first diameter;

a cylindrical lower first portion having the first diameter;

an annular groove interposed between the cylindrical upper first portion and the cylindrical lower first portion; and

the first section having a first length;

a second section formed in the interior surface of the circumscribing sidewall distal to the first section, the second section having a second diameter and the second section having a second length;

wherein the second diameter is at a widest portion of the second section; and

wherein the second diameter is smaller than the first diameter;

a first working surface formed in the circumscribing sidewall;

an axial stop surface formed in the interior surface of the circumscribing sidewall at an interface of the first section and the second section;

a third section formed in the interior surface of the circumscribing sidewall distal to the second section, the third section having a third length;

a sealing seat formed in the interior surface of the circumscribing sidewall and interposed between the second section and the third section, the sealing seat comprising:

an upper annular sealing seat edge at an interface with the second section;

a lower annular sealing seat edge distal to the upper annular sealing seat edge;

a sealing seat surface interposed between the upper annular sealing seat edge and the lower annular sealing seat edge;

wherein the upper annular sealing seat edge is greater in diameter than a narrowest portion of the sealing seat surface;

wherein a fourth length along the central longitudinal axis of the pipette tip between the upper annular sealing seat edge and the lower annular sealing seat edge is less than the second length; and

wherein the fourth length is less than the third length; and

at least one frustoconical section formed in the interior surface of the circumscribing sidewall and between the third section and the open distal end;

wherein at least a portion of the first working surface is configured to receive a first radial force and a first axial force from a coupling device inserted into the open interior passage of the pipette tip to secure the pipette tip against the coupling device;

wherein the first radial force is directed outward and perpendicular from the central longitudinal axis;

wherein the first axial force is directed upward and parallel to the central longitudinal axis;

wherein the sealing seat is configured for receiving a second radial force and a second axial force when a coupling device is inserted into the pipette tip to seal the coupling device against the sealing seat of the pipette tip;

wherein the second radial force is directed outward and perpendicular from the central longitudinal axis; and

wherein the second axial force is directed downward and parallel to the central longitudinal axis.

2 . The pipette tip of claim 1 wherein the axial stop surface is an annular, planar surface perpendicular to the central longitudinal axis of the pipette tip.

3 . The pipette tip of claim 1 wherein the second length is less than the first length.

4 . The pipette tip of claim 3 wherein the third length is greater than the first length.

5 . The pipette tip of claim 4 wherein the sealing seat surface is an annular concave surface.

6 . The pipette tip of claim 3 further comprising:

an annular chamfered interior surface formed in the interior surface of the circumscribing sidewall extending radially inward from the open proximal end and terminating at a proximal end of the first section;

wherein the axial stop surface is an annular, planar surface perpendicular to the central longitudinal axis of the pipette tip.

7 . The pipette tip of claim 3 wherein the sealing seat surface is an annular convex surface.

8 . The pipette tip of claim 3 wherein the sealing seat surface is a frustoconical annular surface.

9 . The pipette tip of claim 3 further comprising an annular chamfered interior surface formed in the interior surface of the circumscribing sidewall extending radially inward from the open proximal end and terminating at a proximal end of the first section.

10 . The pipette tip of claim 3 further comprising:

an annular chamfered interior surface formed in the interior surface of the circumscribing sidewall extending radially inward from the open proximal end and terminating at a proximal end of the first section;

wherein the axial stop surface is an annular, planar surface perpendicular to the central longitudinal axis of the pipette tip; and

wherein the sealing seat surface is an annular concave surface.

11 . The pipette tip of claim 3 further comprising:

an annular chamfered interior surface formed in the interior surface of the circumscribing sidewall extending radially inward from the open proximal end and terminating at a proximal end of the first section;

wherein the axial stop surface is an annular, planar surface perpendicular to the central longitudinal axis of the pipette tip; and

wherein the sealing seat surface is an annular convex surface.

12 . The pipette tip of claim 1 further comprising:

an annular chamfered interior surface formed in the interior surface of the circumscribing sidewall extending radially inward from the open proximal end and terminating at a proximal end of the first section;

wherein the axial stop surface is an annular, planar surface perpendicular to the central longitudinal axis of the pipette tip; and

wherein the sealing seat surface is a frustoconical annular surface.

13 . The pipette tip of claim 1 is made from an electrically conductive material.