Multi-layer devices and methods of assaying for fructosamine

A multi-layer test device for analyzing the concentration of fructosamine in a liquid sample, comprising:

• a buffer layer containing a buffer having a pH value of at least 9;
• an indicator layer containing an indicator capable of being reduced by fructosamine;
• and
• a support member optionally having a detection aperture;
• wherein the buffer layer and the indicator layer are juxtaposed.

A multi-layer test device for analyzing the concentration of fructosamine in a liquid sample, comprising:

• a plastic first substantially planar support member having a sample aperture;
• a plastic second substantially planar support member having a detection aperture;
• a non-opaque, liquid permeable buffer layer containing a buffer having a pH value of between about 10 and about 12;
• and
• an indicator layer containing a nitroblue tetrazolium chloride dye, wherein the buffer layer is superposed above the indicator layer and wherein the buffer layer and indicator layer are sandwiched between the first support member and the second support member.

A method for analyzing the concentration of fructosamine in a liquid sample, comprising the steps of:

• (a) providing a test device having a non-opaque, liquid permeable buffer layer containing a buffer having a pH value of at least 9, an indicator layer containing an indicator capable of being reduced by fructosamine, and a support member optionally having a detection aperture, wherein the buffer layer is superposed above the indicator layer;
• (b) applying a liquid sample to the test device;
• and
• (c) analyzing the indicator layer for the concentration of fructosamine present in the liquid sample.

A method for analyzing the concentration of fructosamine in a liquid sample, comprising the steps of:

• (a) providing a test device having a buffer layer containing a buffer having a pH value of at least 9, an indicator layer containing an indicator capable of being reduced by fructosamine, and a support member optionally having a detection aperture, wherein the buffer layer and the indicator layer are juxtaposed;
• (b) applying a liquid sample to the test device;
• and
• (c) analyzing the indicator layer for the concentration of fructosamine present in the liquid sample.