Multilayer analytical element

Claim 2

A multilayer analytical element for fluorometric assay of an analyte contained in an aqueous sample liquid, the assay comprising a stage of subjecting the analyte, a predetermined amount of a fluorescent-labelled analyte substance or analogue thereof, and a predetermined amount of a protein specifically bindable to the analyte to competitive binding reaction, a stage of substantially separating the resulting bound fluorescent-labelled complex (B) of the protein from the free fluorescent-labelled analyte substance or analogue thereof (F), and a stage of determining the fluorescence strength of said labelled complex (B), which comprises: a porous fibrous or non-fibrous spreading sheet containing a predetermined amount of the fluorescent-labelled analyte substance or analogue thereof; a porous sharing sheet enabling said substantial separation of the bound fluorescent-labelled complex (B) of the protein from the free fluorescent-labelled analyte substance or analogue thereof (F); and a reaction sheet containing a predetermined amount of the protein specifically bindable to the analyte fixed therein; being under laminated structure in this order.

Claim 3

The multilayer analytical element as claimed in Claim 1, in which said analayte is an antigen, said protein is an antibody, said fluorescent-labelled analyte substance or analogue thereof is a fluorescent-labelled antigen or analogue of the antigen, and said binding reaction is an antigen-antibody reaction.

Claim 4

The multilayer analytical element as claimed in Claim 1 or 2, in which said substantial separation of the bound fluorescent-labelled complex (B) from the free fluorescent-labelled analyte substance or analogue thereof (F) is accomplished through sharing of the free fluorescent-labelled analyte substance or analogue thereof between the reaction sheet and other space than the reaction sheet.

Claim 5

The multilayer analytical element as claimed in Claim 3, in which said separation is accomplished through adjusting the ratio of the liquid-holding capacity between the the porous sharing sheet and the reaction sheet to a value within the range of 10 : 1 to 0.5 : 1.

Claim 6

The multilayer analytical element as claimed in Claim 4, in which said assay comprises determination of a total value of the fluorescence strength of the bound fluorescent-labelled complex (B) and the fluorescence strength of the free fluorescent-labelled analyte substance or analogue thereof (F), both being present in the reaction sheet.

Claim 7

The multilayer analytical element as claimed in Claim 1 or 2, in which said spreading sheet shows a higher spreading rate in the direction vertical to the sheet surface than the sharing sheet or reaction sheet does.

Claim 8

The multilayer analytical element as claimed in Claim 1 or 2, in which said sharing sheet is made of a porous fibrous material.

Claim 9

The multilayer analytical element as claimed in Claim 7, in which said sharing sheet contains fine granular particles independently distributed within the porous fibrous material.

Claim 10

The multilayer analytical element as claimed in Claim 7, in which said sharing sheet contains water- insoluble light-blocking material.

Claim 11

The multilayer analytical element as claimed in Claim 9, in which said light-blocking material is capable of absorbing either or both of a light for exciting the bound fluorescent-labelled complex (B) and a radiation emitted by the bound fluorescent-labelled complex (B).

Claim 12

The multilayer analytical element as claimed in Claim 9, in which said light-blocking material is material capable of scattering a light for exciting the bound fluorescent-labelled complex (B) or a radiation emitted by the bound fluorescent-labelled complex (B).

Claim 13

The multilayer analytical element as claimed in Claim 1 or 2, in which said reaction sheet is made of a porous fibrous material.

Claim 14

The multilayer analytical element as claimed in Claim 12, in which said reaction sheet contains fine particles independently distributed within the porous fibrous material.

Claim 15

The multilayer analytical element as claimed in Claim 12, in which said porous fibrous material has a porosity of at least 60 percent in volume.

Claim 16

The multilayer analytical element as claimed in Claim 13, in which said fine particles are of water- insoluble polysaccharide or its derivative.

Claim 17

The multilayer analytical element as claimed in Claim 15, in which the surface of said fine particles are coated in part with a protein bindable to the analyte in the sample liquid through physical adsorption or chemical linkage.

Claim 18

The multilayer analytical element as claimed in Claim 1 or 2, in which a porous light-shielding sheet containing a material capable of absorbing or scattering either or both of a light for exciting the bound fluorescent-labelled complex (B) and a radiation emitted by the bound fluorescent-labelled complex (B) is provided between the sharing sheet and the reaction sheet.

Claim 19

The multilayer analytical element as claimed in Claim 1 or 2, in which a sheet having openings for introduction of the sample liquid in the range of 0.00001 - 0.05 cm 2 is provided between the spreading sheet and the sharing sheet for assisting substantially uniform sharing.

Claim 20

The multilayer analytical element as claimed in Claim 1 or 2, in which a light-transmissive, water-impermeable support is provided to the outer surface of the reaction sheet.

Claim 21

The multilayer analytical element as claimed in Claim 19, in which said support has at least one opening.

Claim 22

A slide for fluorometric assay of an analyte contained in an aqueous sample liquid, in which a multilayer analytical element comprising: a porous fibrous or non-fibrous spreading sheet containing a predetermined amount of the fluorescent-labelled analyte substance or analogue thereof; a porous sharing sheet enabling said substantial separation of the bound fluorescent-labelled complex (B) of the protein from the free fluorescent-labelled analyte substance or analogue thereof (F); and a reaction sheet containing a predetermined amount of the protein specifically bindable to the analyte fixed therein; being under laminated structure in this order is provided in a frame having an opening for introduction of the sample liquid and an opening for enabling fluorometric measurement.

Claim 23

A slide for fluorometric assay of an analyte contained in an aqueous sample liquid, in which a multilayer analytical element comprising: a porous fibrous or non-fibrous spreading sheet containing a predetermined amount of the fluorescent-labelled analyte substance or analogue thereof; a porous sharing sheet enabling said substantial separation of the bound fluorescent-labelled complex (B) of the protein from the free fluorescent-labelled analyte substance or analogue thereof (F); and a reaction sheet containing a predetermined amount of the protein specifically bindable to the analyte fixed therein; being under laminated structure in this order is provided in a frame having an opening for introduction of the sample liquid and an opening for enabling fluorometric measurement.

Claim 24

A slide for fluorometric assay as claimed in Claim 21, said frame comprises a member having an opening for introduction of the sample liquid and a member having an opening for enabling fluorometric measurement, being united through an adhesive material or direct fusion therebetween.

Claim 25

A slide for fluorometric assay as claimed in Claim 22, the frame member contains a coloring material which does not reflect a light for exciting the bound fluorescent-labelled complex (B).

Claim 26

A fluorometic assay of an analyte contained in an aqueous sample liquid comprising a stage of subjecting the analyte, a predetermined amount of a fluorescent-labelled analyte substance or analogue thereof, and a predetermined amount of a protein specifically bindable to the analyte to a competitive binding reaction, a stage of substantially separating the resulting bound fluorescent-labelled complex (B) of the protein from the free fluorescent-labelled analyte substance or analogue thereof (F), and a stage of determining the fluorescence strength of said labelled complex (B), which is chracterized by: employing a multilayer analytical element comprising: a porous fibrous or non-fibrous spreading sheet containing a predetermined amount of the fluorescent-labelled analyte substance or analogue thereof; a porous sharing sheet enabling said substantial separation of the bound fluorescent-labelled complex (B) of the protein from the free fluorescent-labelled analyte substance or analogue thereof (F); a reaction sheet containing a predetermined amount of the protein specifically bindable to the analyte fixed therein; being under laminated structure in this order, and accomplishing said substantial separation of the bound fluorescent-labelled complex (B) from the free fluorescent-labelled analyte substance or analogue thereof (F) through sharing of the free fluorescent-labelled analyte substance or analogue thereof (F) between the reaction sheet and other space than the reaction sheet.

Claim 27

A fluorometic assay of an analyte contained in an aqueous sample liquid comprising a stage of subjecting the analyte, a predetermined amount of a fluorescent-labelled analyte substance or analogue thereof, and a predetermined amount of a protein specifically bindable to the analyte to a competitive binding reaction, a stage of substantially separating the resulting bound fluorescent-labelled complex (B) of the protein from the free fluorescent-labelled analyte substance or analogue thereof (F), and a stage of determining the fluorescence strength of said labelled complex (B), which is chracterized by: employing a multilayer analytical element comprising: a porous fibrous or non-fibrous spreading sheet containing a predetermined amount of the fluorescent-labelled analyte substance or analogue thereof; a porous sharing sheet enabling said substantial separation of the bound fluorescent-labelled complex (B) of the protein from the free fluorescent-labelled analyte substance or analogue thereof (F); a reaction sheet containing a predetermined amount of the protein specifically bindable to the analyte fixed therein; being under laminated structure in this order, and accomplishing said substantial separation of the bound fluorescent-labelled complex (B) from the free fluorescent-labelled analyte substance or analogue thereof (F) through sharing of the free fluorescent-labelled analyte substance or analogue thereof (F) between the reaction sheet and other space than the reaction sheet.