Test strip and method for manufacturating test strips

Inventors

LIN, Wen-Guay

Assignees

Microlife Corp

Abstract

The application discloses a test strip and a method for manufacturing the test strip. The test strip comprises a base layer; an intermediate layer overlaid on the base layer; a blood retaining layer comprising a slit and a blood retaining region fluidly commuted with the slit and overlaid on the intermediate layer; an upper layer overlaid on the blood retaining layer; a reagent disposed on a surface of the intermediate layer and exposed to the slit, wherein there are an expectedly predetermined depth and a measured depth from an interface between the slit and the upper layer to an upper surface of the intermediate layer; and a classification mark representing a compensation factor and disposed on an upper surface of the upper layer or a lower surface of the base layer; wherein the compensation factor is the product of a difference between the predetermined depth and the measured depth and a reciprocal of the predetermined depth.

Core Innovation

The invention relates to a multi-layer blood glucose test strip in which a base layer, an intermediate layer, a blood retaining layer with a slit and a blood retaining region, and an upper layer are stacked such that blood is fluidly commuted with the slit and supplied to a reagent. The reagent is disposed on a surface of the intermediate layer and exposed in the slit. The strip defines a predetermined depth from an interface between the slit and the upper layer to an upper surface of the reagent, and also defines an actual depth from the same interface to the upper surface of the reagent.

To address optical-path length errors caused by mismatch between predetermined depth and actual depth, the strip includes a classification mark representing a correction factor. The correction factor is the product of a difference between the predetermined depth and the actual depth and a reciprocal of the predetermined depth. The classification mark is disposed on an upper surface of the upper layer or a lower surface of the base layer so that device-based recognition can use the correction factor to compensate an optical measurement performed for a colorimetric glucose readout.

The optical glucose detection is described in connection with colorimetric analysis based on Beer-Lambert law, where optical path length is affected by the depth relationship. The correction factor and its representation by the classification mark enable correction/compensation during a readout that uses an optical-path length L concept. The document further describes forming the classification mark as a device-recognizable pattern on the strip, and computing the correction factor from measured actual depth relative to the predetermined depth.

A manufacturing approach is also described for producing such strips in mass-produced sheet-shaped articles. In the method, the actual depth from the interface to the upper surface of the reagent is measured for each test strip, and a correction factor is calculated using the predetermined depth and the actual depth. A corresponding classification mark is labeled on each test strip according to the correction factor, and the sheet-shaped article is divided and cut into individual unit strips.

Claims Coverage

The document provides two independent claims: one to a test strip structure and one to a manufacturing method. Together, the independent claims define the multi-layer slit-based blood retaining structure, the predetermined-versus-actual depth concept, and a classification mark that represents a correction factor, with the second claim applying these concepts in manufacturing through depth measurement, correction-factor calculation, labeling, and cutting.

Across the independent claims, the inventive concept is expressed as a slit-based multi-layer test strip having predetermined depth versus actual reagent depth, plus a classification mark representing a correction factor computed from that depth relationship. The second independent claim operationalizes the same relationship during manufacturing by measuring actual depth, calculating the correction factor, labeling the classification mark accordingly, and cutting the sheet into individual test strips.

Stated Advantages

Documented Applications