Method for collecting interstitial fluid from the skin

• US 6,334,851 B1
• Filed: 05/10/2000
• Issued: 01/01/2002
• Est. Priority Date: 05/10/1999
• Status: Expired due to Fees

• Current Assignee: Microfab Technologies, Inc.
• Original Assignee: Microfab Technologies, Inc.
• Inventors: Taylor, David W., Wallace, David B., Hayes, Donald J.
• Primary Examiner(s): Winakur, Eric F.
• Assistant Examiner(s): MARMOR II, CHARLES ALAN
• Application Number:
  US09/567,915
• Time in Patent Office: 601 Days
• Field of Search: 600/309, 600/310, 600/573, 606/2, 606/9, 606/10, 604/19
• US Class Current: 600/573
• CPC Class Codes: A61B 10/0045 Devices for taking samples of body liquids devices for taking blood samples A61B5/15
• CPC Class Codes: A61B 2010/008 Interstitial fluid
• CPC Class Codes: A61B 2017/00765 Decreasing the barrier function of skin tissue by radiated energy, e.g. using ultrasound, using laser for skin perforation
• CPC Class Codes: A61B 2017/22089 Gas-bubbles

Abstract

A carrier film has one or more openings or wells loaded with a meltable absorbing substance for absorbing laser energy. The carrier film has a clear film which covers one side of the opening containing the absorber substance and the open side of the opening in the carrier film is positioned adjacent to the skin and irradiated through the clear cover film by a laser beam. The melted laser energy absorbing substance is ejected to form a spot laying on the skin. After moving the carrier film, a laser beam impinges the spot thereby raising a tiny blister on the skin containing interstitial fluid. The interstitial fluid is collected for diagnosis and analysis. A method of making and loading the carrier film with a digitally operated dispenser of the type used for ink jet printing is disclosed. Special construction of the opening appears to enhance ejection.

Claims

1. A method for releasing interstitial fluid from skin for collection or measurement, comprising:

providing a carrier film having at least one opening containing a meltable absorber substance selected to absorb energy from a laser beam;

placing the carrier film over skin with the absorber substance positioned facing the skin;

positioning a laser over the carrier film with the beam it produces directed upon the absorber substance; and

melting the absorber substance by means of the laser beam and thereby ejecting the melted absorber substance from the at least one opening in the carrier film to the skin where it becomes a spot which can be used to absorb laser energy in a subsequent step to release interstitial fluid from the skin.

2. The method of claim 1 wherein the step of providing a carrier film comprises the step of providing clear polymer film on one side of said opening and the step of positioning the laser comprises the step of positioning the beam produced by the laser to pass through the clear film before it reaches the absorber substance.

3. The method of claim 2 wherein the step of providing a carrier strip with at least one opening comprises the step of providing said at least one opening with a nozzle and the step of melting the absorber substance and ejecting the melted absorber substance from the at least one opening is carried out by ejecting the absorber substance through the nozzle.

4. The method of claim 2 wherein the step of positioning the laser over the carrier film includes the step of focusing the beam it produces and the step of melting the absorber substance is performed with the focused laser beam.

5. The method of claim 1 wherein the step of providing the carrier film comprises the step of providing a carrier film having a plurality of said openings containing said meltable absorber substance and further includes the step of indexing the carrier film to position the laser with the beam it produces directed to a different opening containing said meltable absorber substance after melting and ejecting the absorber substance from an opening to which the laser beam the laser produces was previously directed.

6. The method of claim 5 wherein the step of providing a carrier film comprises the step of providing a clear polymer film on one side of said plurality of openings and the step of positioning the laser comprises the step of positioning the beam produced by the laser to pass through the clear polymer film before it reaches the absorber substance in any of the plurality of openings.

7. The method of claim 1 wherein the step of providing the carrier film comprises the step of providing a carrier strip having a plurality of said openings containing a meltable absorber substance arranged in a row and includes at least one aperture between a first one of said plurality of openings and a second one of said plurality of openings, further including the steps of:

operating the laser while directing the beam produced by the laser to the first one of said plurality of openings and thereby melting and ejecting the meltable absorber substance from the opening to form a spot of absorber substance on a person'"'"'s skin; and

placing the aperture between said first and second ones of said plurality of openings directly over the spot on a person'"'"'s skin.

8. The method of claim 7 further comprising the step of operating the laser while directing the beam produced by the laser to the spot on the person'"'"'s skin to form a small blister containing interstitial fluid.

9. The method of claim 8 further including the step of taking the interstitial fluid for analysis.

10. A method for releasing interstitial fluid from skin for collection or measurement, comprising:

providing a carrier film having at least one opening containing a meltable absorber substance selected to absorb energy from a laser beam, and at least one aperture in the carrier film adjacent said at least one opening;

placing the carrier film over skin with the absorber substance positioned facing the skin;

positioning a laser over the carrier film with the beam it produces directed upon the absorber substance;

melting the absorber substance by means of a laser beam and thereby ejecting the melted absorber substance from the at least one opening in the carrier film to the skin where it becomes a spot capable of absorbing laser energy;

indexing the carrier film relative to the skin so that the aperture is located between the spot of absorber substance on the skin and the beam produced by the laser; and

operating the laser, while directing the beam produced by the laser to the spot of absorber substance on the skin, to thereby create a tiny blister containing interstitial fluid on the skin in the area where the spot was formed.

11. The method of claim 10 further including the step of taking the interstitial fluid from the blister for analysis.

12. The method of claim 10 wherein the step of providing a carrier film having at least one opening comprises the step of providing clear polymer film on one side of said opening and the step of positioning the laser comprises the step of positioning the beam produced by the laser to pass through the clear film before it reaches the absorber substance.

13. The method of claim 10 wherein the step of providing a carrier film comprises the step of providing a carrier film having a plurality of said openings containing said meltable absorber substance and the step of positioning the laser over the carrier film comprises the step of positioning the beam produced by the laser to pass through the clear polymer film before it reaches the absorber substance in any given one of the plurality of openings.