The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 02, 2003
Filed:
Aug. 03, 1999
Omar S. Khalil, Libertyville, IL (US);
Xiaomao Wu, Gurnee, IL (US);
Shu-jen Yeh, Grayslake, IL (US);
Charles F. Hanna, Libertyville, IL (US);
Stanislaw Kantor, Buffalo Grove, IL (US);
Tzyy-Wen Jeng, Vernon Hills, IL (US);
Abbott Laboratories, Abbott Park, IL (US);
Abstract
A method and apparatus for the measurement of trans-cutaneous diffuse reflectance at a single sampling distance for determining the concentration of an analyte in a biological sample, such as, for example, human tissue. The determination of the concentration of the analyte has been found to depend on the sampling distance and reaches an optimal result at a defined sampling distance for a given analyte and a given sample. The method involves measuring the light re-emitted from the sample at a distance from a light introduction site and correlating the intensity of the re-emitted light to the concentration of an analyte. For a given sample, the distance between the light collection site and a light introduction site (i.e., the sampling distance) corresponds to the depth from the surface into the sample at which scattering and absorption events significantly affect the intensity of re-emitted light (i.e., the sampling depth). Prior knowledge about the sample determines the optimal sampling depth for performing a measurement for a specific analyte and the corresponding sampling distance needed to reach that optimal sampling depth. Optimization of the sampling distance, as well as the correlation relationship, can be established in a calibration procedure.