Method and apparatus for obtaining biological fluids

• US 5,913,833 A
• Filed: 02/07/1997
• Issued: 06/22/1999
• Est. Priority Date: 02/07/1997
• Status: Expired due to Fees

• Current Assignee: Abbott Laboratories Incorporated
• Original Assignee: Abbott Laboratories Incorporated
• Inventors: Elstrom, Tuan A., Shain, Eric B.
• Primary Examiner(s): HINDENBURG, MAX F
• Application Number:
  US08/798,403
• Time in Patent Office: 865 Days
• Field of Search: 600/562, 600/573, 600/576, 600/578, 600/579, 604/19, 604/22, 604/289, 604/290, 604/313
• US Class Current: 600/573
• CPC Class Codes: A61B 2010/008 Interstitial fluid
• CPC Class Codes: A61B 5/14514 using means for aiding extraction of interstitial fluid, e.g. microneedles or suction
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/150083 by vibration, e.g. ultrasound
• CPC Class Codes: A61B 5/150343 Collection vessels for collecting blood samples from the skin surface, e.g. test tubes, cuvettes sampling from within body cavities A61B5/150015, A61B5/150045
• CPC Class Codes: A61B 5/150412 Pointed piercing elements, e.g. needles, lancets for piercing the skin blade-like piercing elements A61B5/150442
• CPC Class Codes: A61B 5/150748 Having means for aiding positioning of the piercing device at a location where the body is to be pierced means for aiding positioning of devices for bringing media into the body A61M5/427, locating blood vessels A61B5/489
• CPC Class Codes: A61B 5/150755 Blood sample preparation for further analysis, e.g. by separating blood components or by mixing
• CPC Class Codes: A61B 5/15107 Piercing being assisted by a triggering mechanism
• CPC Class Codes: A61B 5/15121 comprising piezos
• CPC Class Codes: A61B 5/15186 Devices loaded with a single lancet, i.e. a single lancet with or without a casing is loaded into a reusable drive device and then discarded after use; drive devices reloadable for multiple use
• CPC Class Codes: A61M 2037/0007 having means for enhancing the permeation of substances through the epidermis, e.g. using suction or depression, electric or magnetic fields, sound waves or chemical agents
• CPC Class Codes: A61M 37/0092 using ultrasonic, sonic or infrasonic vibrations, e.g. phonophoresis

Abstract

This invention provides a method and apparatus for disrupting the outermost layer of skin, the stratum corneum, to provide access to biological fluid, which can then be used to determine the concentration of glucose in blood. The invention can be used to extract interstitial fluid, blood, and mixtures of interstitial fluid and blood from the body of a human or an animal.

The method comprises the steps of (1) attaching a receptacle for collecting biological fluid to the surface of the skin of a patient, (2) introducing an oscillation concentrator attached to an oscillation element into the receptacle, (3) positioning the oscillation concentrator at a desired distance from the surface of the skin, (4) activating the oscillation element to transversely oscillate the attached oscillation concentrator, (5) collecting the biological fluid after a specific period of time, and (6) analyzing the biological fluid for the presence of an analyte.

Claims

1. A method for obtaining fluid from the body of a patient for diagnostic purposes, said method comprising the steps of:

(1) attaching a receptacle to the surface of the skin of a patient,

(2) introducing an oscillation concentrator attached to an oscillation element into the receptacle,

(3) positioning the oscillation concentrator at a desired distance from the surface of the skin,

(4) activating the oscillation element to transversely oscillate the attached oscillation concentrator,

(5) collecting the fluid after a specific period of time, and

(6) analyzing the fluid for the presence of an analyte.

2. The method of claim 1, wherein said fluid is interstitial fluid.

3. The method of claim 1, wherein said fluid is blood.

4. The method of claim 1, wherein said receptacle contains a coupling medium.

5. The method of claim 4, wherein said coupling medium is a liquid.

6. The method of claim 1, wherein said oscillation concentrator is a needle having a proximal end and a distal end.

7. The method of claim 1, wherein the distal end of said needle is positioned at a distance ranging from about 0.1 μ

m to about 1000 μ

m from the surface of the skin.

8. The method of claim 1, wherein said oscillation concentrator is caused to oscillate at a frequency of 1×

10² cycles per second to about 1×

10⁹ cycles per second.

9. The method of claim 1, wherein said oscillation element is an ultrasonic horn.

10. The method of claim 1, wherein said oscillation element is a piezoelectric transducer.

11. An apparatus for obtaining fluid from the body of a patient, said apparatus comprising:

(a) an oscillation concentrator having a proximal end and a distal end and having

(b) an electromechanical transducer attached at the proximal end of said oscillation concentrator, said oscillation concentrator capable of oscillating in a transverse mode, said oscillation concentrator being of solid construction.

12. The apparatus of claim 11, wherein said electro-mechanical transducer is an ultrasonic horn.

13. The apparatus of claim 11, wherein said electromechanical transducer is a piezoelectric crystal.

14. The apparatus of claim 13, wherein said piezoelectric crystal is excited by voltage.

15. The apparatus of claim 14, wherein said voltage is applied via electrodes attached to said piezoelectric crystal, thereby causing the crystal to expand and contract in synchrony with the source of excitation, thereby resulting in vibration of said oscillation concentrator.

16. The apparatus of claim 15, wherein said piezoelectric crystal transfers vibration to said oscillation concentrator, thereby causing freely transverse displacement of the distal end of said oscillation concentrator.

17. The apparatus of claim 11, wherein said oscillation concentrator is a needle having a proximal end and a distal end.

18. An apparatus for obtaining fluid from the body of a patient, said apparatus comprising:

(a) an oscillation concentrator having a proximal end and a distal end and having

(b) an electromechanical transducer attached at the proximal end of said oscillation concentrator, said oscillation concentrator capable of oscillating in a transverse mode, wherein said oscillation concentrator is immersed in a reservoir containing a coupling medium in such a manner that the coupling medium is in contact with the surface of human or animal skin.

19. The apparatus of claim 18, wherein the coupling medium is a liquid.