Patent TW-200944790-A (TW)
Title: Method and system of manufacturing test strip lots having a predetermined calibration characteristic
Inventor: MACFIE GAVIN
IPC: G01N33/487
Filed: 2009-01-16
Abstract: Applicants have discovered various embodiments of a technique in which test strip lots can be prepared that do not require a user to input any calibration information before performing a test measurement. In particular, applicants have discovered that, in a generally well-controlled test strip manufacturing process, a high percentage of test strip lots can be produced that have a relatively constant batch slope and batch intercept. In a first aspect, there is provided a method of manufacturing a plurality of test strips, the method comprising: adjusting a working electrode area to output a batch slope that falls within a predetermined target batch slope range; and/or adjusting an amount of mediator in a reagent ink, to output a batch intercept that falls within a predetermined target batch intercept. In a further aspect, there is provided a method of manufacturing a plurality of test strips, the method comprising: adjusting a working electrode area to output a batch slope that is substantially equal to a predetermined target batch slope value; and/or adjusting an amount of mediator in a reagent ink, to output a batch intercept that is substantially equal to a predetermined target batch intercept value. In a further aspect, there is provided a method of preparing a reagent ink formulation for use in such a method comprising: (a) preparing reagent ink; (b) if the reagent ink does not have a density above a target threshold or within a target range, adjusting the density of the reagent ink. In a further aspect, there is provided a method of manufacturing a plurality of test strips according to any preceding claim or a method of screen printing a conductive ink onto a substrate to form a test strip, the method comprising: (i) dispensing the conductive ink on a metallic screen and/or dispensing the conductive on a screen the screen being made of a material that does irreversibly deform when subjected to pressures greater than 4 bars by a squeegee; (ii) locating the substrate proximate to the screen; (iii) transferring the conductive ink onto the substrate with a squeegee. In a further aspect, there is provided a test strip or an analyte test strip comprises the following: a substrate; and a carbon ink disposed on the substrate by a squeegee through a metallic screen to define carbon electrode tracks with each carbon electrode track so that any variations in a length (Y2) of the carbon electrode track as measured along a virtual line substantially perpendicular to the axis (L1 or L2) between two side edges (15A or 15B) of a carbon electrode track in one strip compared to a length of a carbon electrode track in other strips of the predetermined sample of test strips is less than about 3.5% or less than about 2.5%. In a further aspect, there is provided a method of performing an analyte measurement, the method comprising: inserting a test strip into a test meter, the test meter configured to not receive a calibration input, the test strip manufactured to a method according to any preceding claim having a calculated enzyme working area and/or and added amount of reduced mediator in the reagent layer in the working electrode; measuring an analyte concentration upon application of a blood sample to an inlet of the test strip.