Method and apparatus for body fluid sampling with improved sensing

1. A device for use with a body fluid sampling device for extracting bodily fluid from an anatomical feature, said device comprising:

a cartridge having a plurality of cavities;

a plurality of penetrating members, at least one of said plurality of penetrating members being contained in one of said plurality of cavities of the cartridge, the penetrating members being slidably movable to extend outward from openings on said cartridge to penetrate tissue;

a plurality of analyte detecting members;

a plurality of sample chambers, each associated with one of said cavities, said sample chambers being positioned along an outer periphery of said cartridge;

wherein at least one of said analyte detecting members forms a portion of one wall of one of said plurality of sample chambers; and

a position sensor coupled to the plurality of penetrating members, and to a processor; the position sensor

and processor measuring a distance from an initialization point to a point of contact of a penetrating member to a target tissue surface, the penetrating member being retracted by a drive force generator to the initialization point with a distance to the target tissue being measured and a depth of penetration of the penetrating member determined.

2. The device of claim 1 further comprising a fluid spreader positioned over at least a portion of said analyte detecting member to urge fluid toward one of the detecting members.

3. The device of claim 1 wherein said penetrating members each have a tip, wherein at least one tip has a starting position in one of said plurality of sample chambers.

4. The device of claim 1 wherein said analyte detecting members are electrochemical.

5. The device of claim 1 wherein at least one of said sample chambers includes an opening on one of its surfaces, said opening leading fluid to an analyte detecting member.

6. The device of claim 1 wherein at least one of said sample chambers includes an opening on one of its surfaces, wherein one of said analyte detecting members is contained within said opening.

7. The device of claim 1 wherein at least one of said sample chambers includes an opening on one of its surfaces, wherein one of said analyte detecting members is visible through said opening.

8. The device of claim 1 wherein at least one of said sample chambers includes an opening on one of its surfaces, wherein one of said analyte detecting members is positioned so that the opening opens directly onto the detecting member.

9. The device of claim 1 further comprising a mesh configured fluid spreader positioned over an analyte sensing member.

10. The device of claim 1 further comprising a penetrating member driver.

11. A device for use with a body fluid sampling device for extracting bodily fluid from an anatomical feature, said device comprising:

a cartridge having a plurality of cavities and a plurality of sample chambers;

a plurality of penetrating members, at least one of said plurality of penetrating members being contained in one of said plurality of cavities, the penetrating members being slidably movable to extend outward from openings on said cartridge to penetrate tissue;

a plurality of analyte detecting members positioned in the plurality of sample chambers;

wherein each of a sample chamber is positioned substantially adjacent an outer periphery of said cartridge;

wherein at least one of said analyte detecting members forms a portion of one wall of one of said plurality of sample chambers; and

a position sensor coupled to the plurality of penetrating members, the position sensor measuring a distance from an initialization point to a point of contact of a penetrating member to a target tissue surface, the penetrating member being retracted by a drive force generator to the initialization point with a distance to the target tissue being measured and a depth of penetration of the penetrating member determined.

12. The device of claim 11 further comprising a plurality of ribs, each associated with one of said sample chambers.

13. A device for use with a body fluid sampling device for extracting bodily fluid from an anatomical feature, said device comprising:

a cartridge having a plurality of sample chambers;

a plurality of penetrating members, at least one of said plurality of penetrating members being contained in said cavities each of a penetrating member being slidably movable to extend outward from an opening on said cartridge to penetrate tissue;

a plurality of analyte detecting members;

wherein each of a sample chamber being positioned substantially adjacent an outer periphery of said cartridge;

at least one opening in one of said sample chambers leading fluid along a fluid path towards one of said analyte detecting members; and

a position sensor coupled to the plurality of penetrating members, the position sensor measuring a distance from an initialization point to a point of contact of a penetrating member to a target tissue surface, the penetrating member being retracted by a drive force generator to the initialization point with a distance to the target tissue being measured and a depth of penetration of the penetrating member determined.

14. The device of claim 13 wherein said fluid path contains a channel sized to hold no more than 1 microliter.