Techniques and devices associated with blood sampling

Abstract

The present invention generally relates to devices and techniques associated with diagnostics, therapies, and other applications, including skin-associated applications, for example, devices for delivering and/or withdrawing fluid from subjects, e.g., through the skin. In some embodiments, the device includes a system for accessing an extractable medium from and/or through the skin of the subject at an access site, and a pressure regulator supported by a support structure, able to create a pressure differential across the skin at at least a portion of the access site. The device may also include, in some cases, a sensor supported by the support structure for determining at least one condition of the extractable medium from the subject, and optionally a signal generator supported by the support structure for generating a signal relating to the condition of the medium determined by the sensor.

What is claimed is: 
     
         1 - 26 . (canceled) 
     
     
         27 . A device for withdrawing blood from the skin and/or from beneath the skin of a subject, the device comprising:
 a fluid transporter, comprising one or more microneedles;   a pre-packaged vacuum chamber having an internal pressure less than atmospheric pressure prior to the point at which the device is used on the subject; and   a storage chamber, separate from the vacuum chamber, for receiving blood withdrawn from the subject via the fluid transporter when the internal pressure from the pre-packaged vacuum chamber is applied to the skin of the subject.   
     
     
         28 . The device of  claim 27 , wherein the device is self-contained. 
     
     
         29 . The device of  claim 27 , wherein the device comprises at least 6 microneedles. 
     
     
         30 . The device of  claim 27 , wherein the internal pressure is less than atmospheric pressure before blood is withdrawn into the device. 
     
     
         31 . The device of  claim 27 , wherein the device is not actuated to form the internal pressure less than atmospheric pressure. 
     
     
         32 . The device of  claim 27 , wherein at least some of the microneedles are solid. 
     
     
         33 . The device of  claim 27 , further comprising a reaction entity contained within the first storage chamber able to react with an analyte contained within the blood, wherein a product of the reaction entity with the analyte is determinable. 
     
     
         34 . The device of  claim 33 , wherein the product is determinable by an external apparatus able to analyze at least a portion of the device. 
     
     
         35 . The device of  claim 33 , wherein the product of the reaction entity with the analyte is determinable as a change in fluorescence, a change in an electrical property, a change in an optical property, and/or a change in a magnetic property. 
     
     
         36 . The device of  claim 33 , wherein the analyte includes glucose and/or oxygen. 
     
     
         37 . The device of  claim 33 , wherein the analyte is an ion. 
     
     
         38 . The device of  claim 33 , wherein the reaction entity includes an antibody, a protein, and/or an enzyme. 
     
     
         39 . The device of  claim 27 , further comprising a potassium sensor able to determine potassium ions within blood contained within the device. 
     
     
         40 . The device of  claim 27 , further comprising a flow controller able to control blood flow into the storage chamber. 
     
     
         41 . The device of  claim 40 , wherein the flow controller comprises a membrane. 
     
     
         42 . The device of  claim 40 , wherein the flow controller comprises a valve. 
     
     
         43 . The device of  claim 27 , wherein the vacuum chamber does not have a variable volume. 
     
     
         44 . The device of  claim 27 , wherein the device is constructed and arranged to prevent blood from entering the vacuum chamber. 
     
     
         45 . The device of  claim 27 , further comprising an activator comprising a component activatable by a subject and a portion that, when activated, fluidly communicates the internal pressure less than atmospheric pressure from the vacuum chamber to the fluid transporter, wherein prior to activating the activator, the internal pressure less than atmospheric pressure from the vacuum chamber is not in fluid communication with the fluid transporter. 
     
     
         46 . The device of  claim 45 , further comprising a support structure constructed and arranged to move the one or more microneedles into contact with the skin, and to withdrawal the one or more microneedles from the skin after contact with the skin.