Method for body fluid sample extraction
An arrangement for producing a sample of body fluid from a wound opening created in a skin surface at a sampling site includes at least one skin-penetration member having a first end configured to pierce the surface of the skin, and a inner lumen in communication with the first end; at least one actuator operatively associated with the at least one skin-penetration member; and at least one catalyst device configured to cause perfusion of body fluid at the sampling site; wherein the at least one actuator is configured to locate the at least one skin-penetration member so as to obstruct the wound opening while transporting body fluid through the inner lumen. Associated methods are also described.
1. A method of sampling body fluid from a wound opening created in a skin surface at a sampling site, the method comprising:
providing an arrangement comprising a plurality of skin-penetration members and a plurality of pre-cocked torsional spring actuators, wherein each of the plurality of torsional spring actuators has a neutral rest position;
automatically or manually initiating a testing sequence;
actuating a first of the plurality of skin-penetration members with a respective torsional spring actuator such that the torsional spring actuator moves from a pre-cocked position to the neutral rest position and drives the skin-penetration member in an arcuate path into the surface of the skin thereby creating the wound opening;
allowing the first skin-penetration member to obstruct the wound opening when the torsional spring actuator is in the neutral rest position; and
transporting body fluid through an inner lumen of the first skin-penetration member.
2. The method of claim 1 , further comprising positioning a footprint over the sampling site prior to actuating the first skin-piercing member.
3. The method of claim 2 , wherein the footprint has an opening, the opening having a diameter or major dimension of about 3-8 mm.
4. The method of claim 3 , wherein the footprint comprises an elastomeric seal.
5. The method of claim 1 , wherein the method is initiated by manually pressing a button.
6. The method of claim 1 , further comprising applying a catalyst, which comprises applying one or more of vacuum pressure, positive pressure, heat, vibration or topical drugs to the sampling site.
7. The method of claim 1 , further comprising applying a catalyst to the sampling site, wherein applying the catalyst comprises applying vacuum pressure to the sampling site with a pump.
8. The method of claim 7 , further comprising quantifying a volume of the body fluid sample.
9. The method of claim 8 , further comprising controlling the application of the catalyst based at least in part on a volume of body fluid extracted.
10. The method of claim 1 , further comprising providing the plurality of skin-penetration members and the plurality of torsional spring actuators operatively arranged on a disposable cartridge, and initiating multiple testing sequences without replacing the cartridge.
11. The method of claim 10 , further comprising moving the cartridge to present a new skin-penetration member and actuator for use after the performance of a preceding testing sequence.
12. The method of claim 1 , further comprising providing a plurality of hubs, wherein each skin-penetration member is attached to a respective hub, and wherein each hub is attached to a respective torsional spring actuator.
13. The method of claim 12 , wherein each hub comprises a reagent pad.