Patent ID: 7374544

Claim:
A body fluid sampling system for use on a tissue site, the system comprising: a controllable, electrically powered drive force generator; a penetrating member operatively coupled to said controllable, electrically powered drive force generator, said controllable, electrically powered force generator moving said penetrating member along a path out of a housing having a penetrating member exit, into said tissue site, stopping in said tissue site, and withdrawing out of said tissue site; and a sample chamber that includes electrodes, has a volume no greater than 1 μL and has an analyte sensor, the sample chamber being positioned to receive fluid from a wound created by said penetrating member, and the analyte sensor and determine a concentration of an analyte in a fluid using a sample of less than 1 μL of the fluid, wherein when the penetrating member is removed from the sample chamber, the electrodes remain in the sample chamber and the volume of the sample chamber is less than 1 μL and a penetrating member sensor coupled to said controllable, electrically powered drive force generator and to a programmable processor, the penetrating member sensor configured to provide information relative to a depth of penetration of a penetrating member through a skin surface, the programmable processor operatively programmed with software that has control instructions for the controllable, electrically powered drive force generator to keep a wound tract created by a penetrating member open for a sufficient time to provide for spontaneous flow of blood for sample capture into an associated sample chamber, wherein the control instructions are selected from at least one of, penetration depth of a penetrating member, velocity of a penetrating member, velocity of a penetrating member in or out of target tissue and a dwell time of a penetrating member in the tissue site.