The disclosure also relates to novel compositions and methods for the single, direct detection of Hemoglobin A1c percentage in a sample, using conversion of functional groups attached to a transitional metal complex, resulting in quantifiable electrochemical signal at two unique potentials, E.sup.o.sub.1 and E.sup.o.sub.2.

Certain embodiments are directed to sensors that enable the use of optimized biocompatible materials such as pre-anodized paper printed electrode transducer to detect binding of a target agent, wherein the surface is modified or functionalized through zero length cross-linker so that it interacts with or specifically binds a target such as sugars (glucose) or glycated proteins (HgbA1c).

Hemoglobin, its variants, and glycated forms of each are determined individually in a multiplex assay that permits correction of the measured level of HbA1c to account for glycated variants and other factors related to the inclusion of the variants in the sample. New antibodies that are particularly well adapted to the multiplex assay are also provided.

An object is to provide an immunochromatographic analysis kit, with which detection with high sensitivity is realized even in the case of a blood analyte containing saliva collected from the inside of an oral cavity, and an immunochromatographic analysis can be performed without pain or stress. The above object was achieved by an immunochromatographic analysis kit wherein an alkyl glucoside and an anionic surfactant are included in at least one of an analyte dilution solution and a part upstream in the development direction of a detection part.

A method for determining the amount of glycated haemoglobin (HbA1c), in whichif requiredthe erythrocytes in a sample are haemolysed, the haemoglobin that is then releasedif requiredis contacted with a proteolytic agent and the glycated haemoglobin degradation products obtained in this way or otherwise are quantified is disclosed. In order to provide such a process and reagents employable therein that has/have the property of sufficient stability of the chemical compounds that are essential to the reaction, for the stabilization of the haemoglobin which is unfolded at a very low pH in the range from 1 to 3, at least one suitable stabilizer is present in the haemolysis solution. Where a leuco dye is used in connection with the determination of the amount of HbA1c, it is proposed that the latter be stabilized with particular phosphine compounds and/or thio compounds, and, in particular embodiments, the requisite proteolytic agent is to be provided in the form of an inactivated protease which is then only reactivated in situ.

Provided is a glycated hemoglobin oxidase with small measurement error or without deviation of the measured value from the true value regarding a sample containing glycated abnormal hemoglobin. Provided are a glycated hemoglobin oxidase comprising an amino acid sequence in which the amino acid at the position corresponding to position 113, 109, 106, or 102 of the amino acid sequence of SEQ ID NO: 1 is substituted with an amino acid other than a positively-charged amino acid, such as glutamic acid, alanine, or aspartic acid as well as a method and a reagent kit for measurement of glycated hemoglobin using such glycated hemoglobin oxidase. The glycated hemoglobin is capable of reacting with various genotypes and enables highly accurate measurement of glycated hemoglobin in a sample containing glycated abnormal hemoglobin.

Methods of detecting and flagging and/or suppressing aberrant results caused by incomplete dispersion of an immunoassay reagent used in a turbidimetric immunoassay are disclosed.

The present disclosure provides a method for measuring an element of a blood cell component and an element of a non-blood cell component in a minute amount of blood, including: providing a minute amount of blood; obtaining a first blood portion and a second blood portion from the minute amount of blood; measuring a first element related to a non-blood cell component in the first blood portion; hemolyzing the second blood portion; and measuring a second element related to a blood cell component in the second blood portion after the hemolysis.

An object is to provide an immunochromatographic analysis device capable of measuring various components contained in various analytes such as blood and urine efficiently in a short measurement time without the need for complicated measurement preparation and operations. The above object was achieved by an immunochromatographic analysis device for developing an analyte-containing solution obtained by diluting an analyte containing a detection target with an analyte dilution solution, wherein a sample addition part contains an anionic surfactant.

Kits, microfluidics devices, and assays for use in methods of spectroscopically determining a ratio of glycated hemoglobin to total hemoglobin in a whole blood sample are disclosed.