ELASTOMERIC TOROIDAL RING FOR BLOOD EXPRESSION

1 . An expression device, comprising:

an expressing cap defining a lancet opening;

the expression cap having a skin contacting surface that is generally flat and positioned to face tissue during expression of body fluid;

the expression cap including an elastomeric ring extending around the lancet opening from the skin contacting surface, wherein the elastomeric ring includes elastomeric material; and

the expression cap having a beveled surface between the lancet opening and the elastomeric ring to enhance expression of the body fluid when the expression cap is pressed around an incision site.

2 . The device of claim 1 , wherein the beveled surface extends at a 20° to 30° angle relative to the skin contacting surface.

3 . The device of claim 1 , wherein the beveled surface extends at a 20° angle relative to the skin contacting surface.

4 . The device of claim 2 , wherein:

the elastomeric ring has a outer diameter of 10 mm;

the elastomeric ring has an inner diameter of 7 mm;

the elastomeric ring has a height of 1.5 mm relative to the skin contacting surface; and

the lancet opening has an internal diameter of 6 mm.

5 . The device of claim 1 , wherein the elastomeric ring is an o-ring.

6 . The device of claim 1 , wherein the expression cap is generally ring-shaped.

7 . The device of claim 1 , further comprising an overmold layer covering the elastomeric ring.

8 . A method, comprising:

forming an incision in skin; and

expressing body fluid from the incision by pressing around the incision in the skin an expression cap that includes an elastomeric ring made from elastomeric material and a beveled surface located inside the elastomeric ring.

9 . The method of claim 8 , wherein:

the expression cap has a generally flat skin contacting surface that extends parallel to the skin when pressed against the skin;

the beveled surface extends at a 20° angle relative to the skin contacting surface; and

said expressing includes pressing the beveled surface against the skin.

10 . The method of claim 9 , further comprising:

pressing the expression cap against the skin before said forming the incision.

11 . The method of claim 9 , wherein said expressing includes pressing the expression cap against the skin for at least 4 seconds.

12 . The method of claim 9 , wherein said forming the incision includes lancing the skin to a depth of 1.8 mm.

13 . The method of claim 8 , further comprising:

wherein the expression cap has a generally flat skin contacting surface that extends parallel to the skin when pressed against the skin;

wherein the beveled surface extends at a 20° angle relative to the skin contacting surface;

wherein said expressing includes pressing the beveled surface against the skin;

pushing the expression cap against the skin before said forming the incision;

wherein said expressing includes pressing the expression cap against the skin for at least 4 seconds; and

wherein said forming the incision includes lancing the skin to a depth of 1.8 mm.

14 . The method of claim 8 , wherein:

the expression cap has a generally flat skin contacting surface that extends parallel to the skin when pressed against the skin;

the beveled surface extends between a 20° to 30° angle relative to the skin contacting surface; and

said expressing includes pressing the beveled surface against the skin.

15 . The method of claim 8 , further comprising testing the body fluid.

16 . The method of claim 8 , wherein said expressing includes pressing the expression cap against the skin until at least 0.1 μL of the body fluid is on the surface of the skin.