Test element for quantitative NIR spectroscopic analysis

• US 5,523,054 A
• Filed: 01/31/1995
• Issued: 06/04/1996
• Est. Priority Date: 01/31/1995
• Status: Expired due to Fees

• Current Assignee: Clinical Diagnostic Systems Inc.
• Original Assignee: Johnson & Johnson Clinical Diagnostics Inc. (Johnson & Johnson)
• Inventors: Switalski, Steven C., Kissel, Thomas R.
• Primary Examiner(s): ALEXANDER, LYLE
• Application Number:
  US08/381,629
• Time in Patent Office: 490 Days
• Field of Search: 250/339.11, 250/341.8, 422/82.05, 422/68.1, 422/55, 422/56, 422/58, 436/164
• US Class Current: 422/82.05
• CPC Class Codes: B01L 3/508 rigid containers not provided for above
• CPC Class Codes: G01N 21/359 using near infrared light
• CPC Class Codes: G01N 21/8483 Investigating reagent band test-element handling not specific to a test method G01N33/4875; analytical elements specific to chemical analysis of biological material G01N33/52; autometer with reagent band G01N35/04
• CPC Class Codes: G01N 33/525 Multi-layer analytical elements
• CPC Class Codes: G01N 35/04 Details of the conveyor system G01N35/021 - G01N35/028 take precedence
• CPC Class Codes: G01N 35/1002 Reagent dispensers

Abstract

There is disclosed a slide test element and method of assay that allows for detection of analytes in biological liquids without the use of any detection reagents. The method uses NIR spectroscopy and a test element comprising a support, and a substantially constant light-path defining layer comprising a diffusely-reflecting material that is a) sufficiently porous in all directions as to allow a liquid to spread uniformly in all directions, and b) homogeneously reflects at least 95% of NIR radiation.

Claims

1. A test element for analyzing analytes in patient samples, comprising, in overlying relation,

a support, and

a substantially constant light-path providing layer consisting essentially of a diffusely-reflecting material that a) is sufficiently porous in all directions as to allow a liquid to spread uniformly in all directions, and b) homogeneously and diffusively reflects at least 95% of NIR radiation,

said element being substantially free of:

i) reagents capable of reacting with said analyte, and ii) a hydrophilic polymer layer that is both separate from said light-path providing layer, and has a thickness equal to or greater than 1 micron,

and further including a mirror layer in-between said light-path providing layer and said support and in contact with said support, effective to increase the path length of NIR radiation through said layer.