Fuji Photo Film Company, Limited

Toru Kitani

Kaoru Terashima

Toshihiro Mori

Yoshihiko Makino

Takao Akagi

Naofumi Hora

Tsuneo Kawase

A dry analysis element for the quantitative analysis of an analyte contained in whole blood comprises a layer exhibiting volume filtration function and a detection layer. The layer exhibiting volume filtration function is made of a cloth selected from microfibrous cloths each having an average fiber diameter of from 0.1 to 10 .mu.m or a napped cloth having an average of from 1 to 30 .mu.m. In a first preferred embodiment, the layer exhibiting volume filtration function is composed of a non-woven cloth having a density of from 0.01 to 0.2 g/cm.sup.3 and made of fibers each having an average fiber diameter of from 0.2 to 10 .mu.m. In a second preferred embodiment, the layer exhibiting volume filtration function is composed of a napped cloth having a fiber density per cm.sup.2 of from 7.0.times.10.sup.3 to 8.2.times.10.sup.6, each of the napped fibers having an average diameter of from 1 to 30 microns and an average nap length of 0.5 to 5.0 mm. In a third preferred embodiment, the layer exhibiting volume filtration function is composed of a cloth having a porosity of from 45 to 70% and made of micro filaments each having an average filament diameter of from 0.1 to 7 .mu.m.

Dry analysis element for quantitative analysis of analyte contained in

An integral multilayer analytical element in which a first fibrous porous layer, a nonfibrous porous layer, and a second fibrous porous layer superposed in this order on a water-impermeable light-transmissive support the first fibrous porous-layer having a larger pore size than the nonfibrous porous layer. The above three porous layers are integrally laminated to each other substantially closely by an adhesive discontinuously disposed so as to form microspaces continuing through from one layer to the next so as not to interfere with the approximately uniform permeation of liquid. A reagent composition which produces an optically detectable change in the presence of an analyte is incorporated in at least one of said three porous layers. When a nonporous reagent layer is incorporated on the support in the above analytical element, the reagent composition is incorporated in the nonporous reagent layer. By using the analytical element of the invention, the analytical values of various analytes of blood samples can be obtained independently of hematocrit values from whole blood samples and blood plasma samples in the range of the hematocrit values of 0% to 55%.

Analytical element for whole blood

An integral multilayer analytical element for the determination of ammonia or an ammonia-producing substance comprising a light-transmissive liquid-impermeable support, an indicator layer containing an indicator which produces a detectable change by gaseous ammonia, a liquid permeation barrier layer, a reagent layer containing an alkaline buffer and optionally a reagent capable of reacting with a substance to produce ammonia and a spreading layer laminated in this order, which is improved by that the indicator layer contains a polyvinyl alkyl ether, and/or which is improved by that the surface of said support facing toward the indicator layer is undercoated with a polyvinyl alkyl ether, a hydroxyalkyl cellulose, an alkyl cellulose, polystyrene, a polyalkyl methacrylate, polyviriylidene chloride, polyvinyl alcohol or polyvinyl pyrrolidone, substantially not containing ammonia and ammonium ion. By using the above analytical element, ammonia or an ammonia-producing substance can be analyzed at a high coloring optical density and a high accuracy. The measuring accuracy is further improved by lowering the background optical density.

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Saitama, Japan

Toru Kitani