Fine-grained filler substances for photometric reaction films

Abstract

There is proposed a diagnostic test element for detecting an analyte in a sample of a body fluid, more particularly in whole blood. The diagnostic test element comprises at least one test field having at least one detection reagent, wherein the detection reagent is set up to pass through at least one detectable change in the presence of the analyte, more particularly an optical change. The test field has at least one detection layer which comprises the detection reagent and which comprises particles. At least 90% of all particles of the detection layer have an actual particle size of less than 10 micrometers.

What is claimed is: 
     
         1 . A diagnostic test element for detecting an analyte in a sample of a body fluid, more particularly in whole blood, comprising at least one test field having at least one detection reagent, wherein the detection reagent is set up to pass through at least one detectable optical change in the presence of the analyte, wherein the test field has at least one detection layer comprising the detection reagent, wherein the detection layer comprises particles, wherein at least 90% of all particles of the detection layer have an actual particle size of less than 10 micrometers, wherein the test field has a loading side for applying the sample and a detection side for detecting an optical change in the detection reagent, wherein the test field further has at least one partition layer, wherein the partition layer is arranged on a side of the detection layer facing the loading side, wherein the partition layer comprises at least one pigment. 
     
     
         2 . The diagnostic test element of  claim 1 , wherein at least 80% of all particles of the detection layer have an actual particle size of less than 5 micrometers. 
     
     
         3 . The diagnostic test element of  claim 1 , wherein at least 80% of all particles of the detection layer have an actual particle size of less than 1 micrometer. 
     
     
         4 . The diagnostic test element of  claim 1 , wherein at least 70% of all particles of the detection layer have an actual particle size of less than 900 nanometers. 
     
     
         5 . The diagnostic test element of  claim 1 , wherein the particles of the detection layer have an average particle size of 10 nanometers to 5 micrometers. 
     
     
         6 . The diagnostic test element of  claim 1 , wherein the particles of the detection layer have an average particle size of 10 nanometers to less than 1 micrometer. 
     
     
         7 . The diagnostic test element of  claim 1 , wherein the particles of the detection layer have an average particle size of less than 1 micrometer. 
     
     
         8 . The diagnostic test clement of  claim 1 , wherein the particles of the detection layer have an average particle size of less than 500 nanometers. 
     
     
         9 . The diagnostic test element of  claim 1 , wherein the particles of the detection layer have an average particle size of up to 300 nanometers. 
     
     
         10 . The diagnostic test element of  claim 1 , wherein the particles comprise one or more of the following materials: SiO 2 ; diatomaceous earth; a silicate; a metal oxide; a synthetic oxidic, material; kaolin; powder glass; precipitated silica; calcium sulfate×2 H 2 O. 
     
     
         11 . The diagnostic test element of  claim 10 , wherein the silicate includes a sodium aluminium silicate. 
     
     
         12 . The diagnostic test element of  claim 10 , wherein the metal oxide includes at least one of an aluminium axide and a titanium oxide. 
     
     
         13 . The diagnostic test element of  claim 10 , wherein the synthetic oxidic material includes a nanoparticulate oxidic material. 
     
     
         14 . The diagnostic test element of  claim 13 , wherein the nanoparticulate oxidic material includes at least one of a nanoparticulate silicon oxide, an aluminum oxide, and a titanium oxide. 
     
     
         15 . The diagnostic test element of  claim 1 , wherein all particles of the detection layer having a particle size of more than 100 nm are inorganic particles. 
     
     
         16 . The diagnostic test element of  claim 1 , wherein the detection layer has a refractive index of between 1.0 and 1.5. 
     
     
         17 . The diagnostic test element of  claim 1 , wherein the detection layer has a refractive index of between 1.2 and 1.4. 
     
     
         18 . The diagnostic test element of  claim 1 , wherein the pigment comprises a white pigment. 
     
     
         19 . The diagnostic test element of  claim 18 , wherein the pigment is selected from one or more of the following pigments: titanium dioxide; zirconium dioxide; barium titanate; barium zirconate; zirconium silicate. 
     
     
         20 . The diagnostic test element of  claim 1 , further comprising at least one support element, wherein the support element has at least one transparent region, wherein the test field is applied at least in part to the transparent region with its detection side. 
     
     
         21 . A process for producing a diagnostic test element for detecting an analyte in a sample of a body fluid, wherein the diagnostic test element comprises at least one test field having at least one detection reagent, wherein the detection reagent is set up to pass through at least one change in the presence of the analyte, wherein the test field has at least one detection layer comprising the detection reagent, wherein the detection layer is generated such that the detection layer comprises particles, wherein at least 90% of all particles of the detection layer have an actual particle size of less than 10 micrometers, wherein the test field has a loading side for applying the sample and a detection side for detecting a change in the detection reagent, wherein the test field further has at least one partition layer, wherein the partition layer is arranged on a side of the detection layer facing the loading side, wherein the partition layer comprises at least one pigment. 
     
     
         22 . The process of  claim 21 , wherein the change in the presence of the analyte and the change in the detection reagent are optical changes. 
     
     
         23 . The process of  claim 21 , wherein at least 90% of all particles of the detection layer have an actual particle size of less than 1 micrometer. 
     
     
         24 . The process of  claim 21 , wherein at least one powder is used to provide the particles, wherein the powder comprises agglomerates of primary particulates, wherein the powder is processed by means of at least one mechanical dispersion process in order to break up the agglomerates at least partly. 
     
     
         25 . The process of  claim 24 , wherein at least one dissolver is used for carrying out the mechanical dispersion process, wherein a dispersion for producing the detection layer is generated. 
     
     
         26 . The process of  claim 21 , wherein at least one powder is used to provide the particles, wherein the powder is subjected to at least one milling step. 
     
     
         27 . The process of  claim 21 , wherein a powder of a synthetic oxidic material is used when providing the particles. 
     
     
         28 . The process of  claim 27 , wherein the synthetic oxidic material is a nanoparticulate oxidic material. 
     
     
         29 . The process of  claim 28 , wherein the nanoparticulate oxidic material includes at least one of a nanoparticulate silicon oxide, an aluminum oxide, and a titanium oxide. 
     
     
         30 . A process for detecting an analyte in a sample of a body fluid such as whole blood, wherein the sample having a volume of less than 2 microliters can be applied to a diagnostic test element to detect the analyte in the sample, the diagnostic test element comprising at least one test field having at least one detection reagent, wherein the detection reagent is set up to pass through at least one detectable change in the presence of the analyte, wherein the test field has at least one detection layer comprising the detection reagent, wherein the detection layer comprises particles, wherein at least 90% of all particles of the detection layer have an actual particle size of less than 10 micrometers, wherein the test field has a loading side for applying the sample and a detection side for detecting a change in the detection reagent, wherein the test field further has at least one partition layer, wherein the partition layer is arranged on a side of the detection layer facing the loading side, wherein the partition layer comprises at least one pigment. 
     
     
         31 . The process of  claim 30 , wherein the volume of the sample is less than 0.5 microliters. 
     
     
         32 . The process as recited in  claim 30 , wherein the detectable change is an optically detectable change, wherein a spatially resolving optical detector is used for detecting the detectable change.