Method for manufacturing a test element for detecting an analyte in a body fluid

Abstract

A method for manufacturing a test element for detecting at least one analyte in a body fluid, a test element for detecting at least one analyte in a body fluid, a method for detecting at least one analyte in a body fluid, a system for detecting at least one analyte in a body fluid and a method for manufacturing a test element for detecting at least one analyte in a body fluid are disclosed. The method for manufacturing a test element for detecting at least one analyte in a body fluid comprises the following steps: a) providing at least one substrate having at least one elongate receptacle on a substrate surface of the substrate; b) placing at least one test chemical on the substrate in a manner that the test chemical covers a partition of the elongate receptacle; c) placing at least one cover element on the substrate such that the cover element covers the elongate receptacle at least partially, whereby a channel having a channel surface is formed; wherein at least one hydrophilic material is applied in a manner that at least one surface section of the channel surface is covered with the hydrophilic material, wherein the surface section is adjacent to the test chemical.

Claims

1. A method for manufacturing a test element for detecting at least one analyte in a body fluid, wherein the method comprises the following steps: providing at least one substrate having at least one elongate receptacle on a substrate surface of the substrate; placing at least one test chemical on the substrate in a manner that the test chemical covers a partition of the elongate receptacle, the test chemical having a test chemical edge; placing a cover element on the substrate coplanar with and laterally displaced from the test chemical, the cover element having a cover edge laterally displaced from the test chemical edge, a lateral gap being formed between the cover edge and the test chemical edge, the cover element covering the elongate receptacle at least partially, whereby a channel having a channel surface is formed; applying at least one hydrophilic material to at least one surface section of the channel surface, wherein the surface section is adjacent to the test chemical; and applying a hydrophilic layer, filling in the area of the gap between the test chemical edge and the cover edge, the hydrophilic layer bridging the gap between the test chemical edge and the cover edge and in such a manner that at least one surface section of the channel surface is covered with the hydrophilic layer.

2. The method according to claim 1, wherein the surface section is a continuous surface section extending from an opening of the channel to the test chemical.

3. The method according to claim 1, wherein the at least one channel surface is formed by at least one surface selected from the group consisting of: the substrate surface, a cover element surface of the cover element, and a receptacle surface of the elongate receptacle.

4. The method according to claim 3, wherein the surface section covered by the hydrophilic material is part of the cover element surface, wherein the hydrophilic material is applied such that the hydrophilic material forms a connection between the surface section and the test chemical.

5. The method according to claim 3, wherein the surface section covered by the hydrophilic material is part of the receptacle surface, wherein the hydrophilic material is applied such that the hydrophilic material forms a connection between the surface section and the test chemical.

6. The method according to claim 1, wherein the hydrophilic material is applied such that further at least one test chemical surface section of at least one test chemical surface of the test chemical is covered with the hydrophilic material.

7. The method according to claim 1, wherein the hydrophilic material is applied on the substrate before the test chemical and the cover element are placed on the substrate, wherein the hydrophilic material is applied such that at least a partition of the elongate receptacle is covered with the hydrophilic material.

8. The method according to claim 1, wherein the test chemical and the cover element form one single element such that the test chemical and the cover element are placed on the substrate as one unit, wherein the hydrophilic material is applied to at least one surface of the single element.

9. The method according to claim 1, wherein the hydrophilic material comprises at least one material selected from the group consisting of: a polymer, a surface-active substance, a filling material, and a reactive component.

10. The method according to claim 9, wherein the polymer is selected from the group consisting of: cellulose, polyethylene glycol, polyvinyl alcohol, polyolefin, polyurethane, polyamide, polyimide, polyacrylate, polycarbonate, polyester, polyether, polyvinyl ether, polyvinyl ester, polyvinyl alcohol, and polysiloxane.

11. The method according to claim 9, wherein the hydrophilic material is an anionic surfactant.

12. A test element for detecting at least one analyte in a body fluid, wherein the test element comprises: at least one substrate having at least one elongate receptacle; at least one test chemical on the substrate and having a test chemical edge, wherein the test chemical covers the elongate receptacle at least partially, a cover element on the substrate, the cover element being coplanar with and laterally displaced from the test chemical, the cover element having a cover edge laterally displaced from the test chemical edge, a lateral gap being formed between the cover edge and the test chemical edge; at least one channel having a channel surface being formed by the cover element covering the elongate receptacle at least partially; at least one hydrophilic material, which is a suspension or solution, configured to cover at least one surface section of the channel surface, wherein the surface section is adjacent to the test chemical; and a hydrophilic layer filling in the area of the gap between the test chemical edge and the cover edge and bridging the gap between the test chemical edge and the cover edge in such a manner that at least one surface section of the channel surface is covered with the hydrophilic layer.

13. A method for detecting at least one analyte in a body fluid, the method comprising the following steps: providing a test element according to claim 12; placing a sample of the body fluid into at least one opening of the channel; transporting the sample of the body fluid to the test chemical; and conducting at least one electrical measurement or at least one optical measurement thereby detecting at least one detection reaction between the test chemical and the sample of the body fluid.

14. A system for detecting at least one analyte in a body fluid, the system comprising at least one test element according to claim 12, the system further comprising at least one measurement device adapted for performing at least one electrical measurement or at least one optical measurement using the test element.

15. The method according to claim 1, wherein the hydrophilic layer is a hydrophilic porous layer.

16. The test element according to claim 12, wherein the hydrophilic layer is a hydrophilic porous layer.

17. A method for manufacturing a test element for detecting at least one analyte in a body fluid, wherein the method comprises the following steps: providing at least one substrate having at least one elongate receptacle on a substrate surface of the substrate; placing at least one test chemical on the substrate in a manner that the test chemical covers a partition of the elongate receptacle, the test chemical comprising a top surface, a bottom surface, and an intervening test chemical edge; placing a cover element on the substrate, the cover element comprising a top surface, a bottom surface, and an intervening cover edge, the cover edge being laterally displaced from the test chemical edge, a lateral gap being formed between the cover edge and the test chemical edge, the cover element covering the elongate receptacle at least partially, whereby a channel having a channel surface is formed; applying at least one hydrophilic material to at least one surface section of the channel surface, wherein the surface section is adjacent to the test chemical; and applying a hydrophilic layer, filling in the area of the gap between the test chemical edge and the cover edge, the hydrophilic layer bridging the gap between the test chemical edge and the cover edge and in such a manner that at least one surface section of the channel surface is covered with the hydrophilic layer.

18. A method for manufacturing a test element for detecting at least one analyte in a body fluid, wherein the method comprises the following steps: providing at least one substrate having at least one elongate receptacle on a substrate surface of the substrate; placing at least one test chemical on the substrate in a manner that the test chemical covers a partition of the elongate receptacle, the test chemical having a test chemical edge; placing a cover element on the substrate adjacent to but laterally displaced from the test chemical such that each of the cover element and the test chemical is positioned adjacent the substrate, the cover element having a cover edge laterally displaced from the test chemical edge, a lateral gap being formed between the cover edge and the test chemical edge, the cover element covering the elongate receptacle at least partially, whereby a channel having a channel surface is formed; applying at least one hydrophilic material to at least one surface section of the channel surface, wherein the surface section is adjacent to the test chemical; and applying a hydrophilic layer filling in the area of the gap between the test chemical edge and the cover edge, the hydrophilic layer bridging the gap between the test chemical edge and the cover edge and in such a manner that at least one surface section of the channel surface is covered with the hydrophilic layer.

Description

SHORT DESCRIPTION OF THE FIGURES

(1) Further optional features and embodiments of the invention will be disclosed in more detail in the subsequent description of preferred embodiments, preferably in conjunction with the dependent claims. Therein, the respective optional features may be realized in an isolated fashion as well as in any arbitrary feasible combination, as the skilled person will realize. The scope of the invention is not restricted by the preferred embodiments. The embodiments are schematically depicted in the Figures. Therein, identical reference numbers in these Figures refer to identical or functionally comparable elements.

(2) In the Figures:

(3) FIGS. 1A to 1E show an exemplary embodiment of a method for manufacturing a test element, wherein different intermediate products and the test element are shown in different perspective views;

(4) FIGS. 2A to 2F show a further exemplary embodiment of a method for manufacturing a test element, wherein different intermediate products and the test element are shown in different perspective views;

(5) FIGS. 3A to 3B show an exemplary embodiment of a test element in a cross-sectional view (FIG. 3A) and in a top-view (FIG. 3B);

(6) FIG. 4A to 4B show a further exemplary embodiment of a test element in a cross-sectional view (FIG. 4A) and in a top-view (FIG. 4B);

(7) FIGS. 5A to 5C show a further exemplary method for manufacturing a test element, wherein different intermediate products and the test element are shown;

(8) FIGS. 6A to 6D show a further exemplary method for manufacturing a test element, wherein different intermediate products and the test element are shown; and

(9) FIGS. 7A and 7B show a remission in dependence of time (FIG. 7A) and a difference of remission (FIG. 7B) for different thicknesses of the hydrophilic layer.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(10) FIGS. 1A to 1E show an exemplary embodiment of a method for manufacturing a test element 110. The test element 110 is illustrated in FIG. 1E in a perspective view. In FIGS. 1A to 1D, different intermediate products 112 of the test element 110 are shown. The intermediate products 112 are illustrated in different perspective views as well.

(11) In a first step, as illustrated in FIG. 1A, at least one substrate 114 is provided. The substrate 114 may specifically be a flat substrate 116 having at least one flat surface 117. A surface of the substrate 114 may also be referred to as substrate surface 118. The substrate surface 118 may specifically extend along a direction of extension 120 of the substrate 114. The substrate 114 may at least partially be manufacturing of at least one hydrophobic material such as polyethylene terephthalate. However, other materials may be feasible. Further, the substrate 114 may have an elongate shape. Exemplarily, the substrate 114 may be strip-shaped.

(12) In a further step, as illustrated in FIGS. 1B and 1C, at least one elongated receptacle 122 may be formed on the substrate surface 118. As illustrated in FIG. 1B, at least one foil 124, specifically at least one adhesive foil 126, may be placed on the substrate 114, specifically on the substrate surface 118 of the substrate 114. The adhesive foil 126 may comprise at least one adhesive surface 128 facing the substrate 114, specifically the substrate surface 118 of the substrate 114. Specifically, the adhesive foil 126 may be a double-sided adhesive foil 130. The double-sided adhesive foil 130 may comprise at least one further adhesive surface 132. The foil 124 may comprise at least one opening 134. The opening 134 may extend in the direction of extension 120. The foil 124 may have a thickness of 20 μm. However, other dimensions may be feasible. The foil 124 may be placed onto the substrate 114. Thereby, the foil 124 may be fixedly attached to the substrate 114 via the adhesive surface 128 of the foil 124. Thereby, the elongate receptacle 122 may be formed, specifically by the opening 134 of the foil 124 and the surface 118 of the substrate 114. The elongate receptacle may have a width of 0.1 mm to 10 mm. Further, the elongate receptacle 122 may have a thickness of 70 μm. However, other dimensions may be feasible.

(13) In a further step, as illustrated in FIG. 1D, at least one hydrophilic material 136 may be applied via spray coating. Specifically, the hydrophilic material 136 may be applied on the substrate 114, specifically on the substrate surface 118. Thereby, the hydrophilic material 136 may be applied such that the elongate receptacle 122 is covered with the hydrophilic material 136 at least to a large extent. The hydrophilic material 136 may specifically be provided as a suspension or as a solution, and the suspension or the solution may be applied via at least one nozzle (not shown). The suspension or the solution may comprise at least one solvent and the solvent may evaporate during the spray coating or may be removed after conducting the spray coating via at least one drying process. Specifically, the solvent may comprise at least one material selected from the group consisting of: a polymer, a surface-active substance, a filling material, a reactive component. However, other embodiments may be feasible. The hydrophilic material 136 may be applied such that at least one hydrophilic layer 162 is formed on the surface section 160. The hydrophilic layer 162 may have a thickness of 1 μm to 10 μm. However, other dimensions may be feasible. Specifically, the hydrophilic layer 162 may be formed as a continuous hydrophilic layer 164.

(14) In a further step, as illustrated in FIG. 1E, at least one test chemical 138 is placed on the substrate 114, such that the test chemical 138 covers a partition 139 of the elongate receptacle 122. The test chemical 138 may be provided as a test chemical element 140. Exemplarily, the test chemical element 140 may be manufactured by depositing the test chemical 138 on at least one test chemical substrate 142. Thus, the test chemical element 140 may be a rigid element 144 which may lay flat on the foil 124. Specifically, the foil 124 may be a double-sided adhesive foil 130 and the test chemical element 140 may be fixedly attached to the double-sided adhesive foil 130 by the further adhesive surface 132.

(15) Further, as illustrated in FIG. 1E, at least one cover element 146 may be placed on the substrate 114, specifically on the substrate surface 118 of the substrate 114. The cover element 146 may cover the elongate receptacle 122 at least partially such that a channel 148 is formed. The cover element 146 may specifically have a flat shape and extend along the direction of extension 120. The cover element 146 may specifically be a rigid element 150 and may lay flat on the foil 124. Specifically, the foil 124 may be a double-sided adhesive foil 130, and the cover element 164 may be fixedly attached to the double-sided adhesive foil 130 via the further adhesive surface 132. The cover element 146 may have a shape which corresponds to a shape of the substrate 114 such as a strip shape and/or a bar shape. Further, specifically, the cover element 146 may have a width which is equivalent to the width of the substrate 114. Further, the cover element 146 may have a length which is smaller than a length of the elongate receptacle, such as by a factor of 1.7. However, other embodiments may be feasible. Specifically, the cover element may at least partially be manufactured of polyethylene glycol. Specifically, the cover element 146 may be placed adjacent to the test chemical 138.

(16) The channel 148 may specifically be a capillary channel 152. The channel 148 may comprise at least one channel surface 154. The at least one channel surface 154 may be formed by at least one surface selected from the group consisting of the substrate surface 118 of the substrate 114, a cover element surface 156 of the cover element 146, a receptacle surface 158 of the elongate receptacle 122. Thereby, the receptacle surface 158 may be at least partially identical to the substrate surface 118. The surface section 160 may specifically be a continuous surface section 159 extending from an opening 161 of the channel 148 to the test chemical 138. At least one surface section 160 of the at least one channel surface 154 of the channel 148 may be covered with the hydrophilic material. The surface section 160 may be adjacent to the test chemical 138. Specifically, the surface section 160 may be part of the receptacle surface 158. Thereby, the hydrophilic material 136 may specifically be applied such that the hydrophilic material 136 forms a connection between the surface section 160 and the test chemical 138. The channel 148 may have a length of 10 mm to 15 mm. A fill time of the channel 148 may be smaller than 5 seconds, preferably smaller than 2 seconds, more preferably smaller than 1.5 seconds.

(17) FIGS. 2A to 2F show a further exemplary embodiment of a method for manufacturing a test element 110. The test element 110 may be depicted in FIG. 2F, and different intermediate products 112 are illustrated in FIGS. 2A to 2E. Firstly, as illustrated in FIG. 2A, the substrate 114 may be provided and the substrate 114 may be covered with the adhesive foil 126 comprising the opening 134. By placing the adhesive foil 126 onto the substrate 114, the elongate receptacle 122 may be formed. These steps may correspond at least in large parts to the steps of the method for manufacturing a test element as illustrated in FIGS. 1A to 1E. Specifically, the steps as illustrated in FIGS. 2A to 2C may correspond to the steps as illustrated in FIGS. 1A to 1C. Thus, reference may be made to the description of FIGS. 1A to 1C above.

(18) In a further step, as illustrated in FIG. 2D, the test chemical 138 and the cover element 146 may be provided. Specifically, the test chemical 138 and the cover element 164 may form a single element 166. Exemplarily, the test chemical 138 and the cover element 146 may be fixedly attached to a support element 168. The support element 168 may specifically be provided as a flat substrate 170. Therefore, the support element 168 may comprise at least one flat surface 172 and the test chemical 138 and the cover element 146 may be fixedly attached to the support element 168 by being placed on the flat surface 142 and adjacent to each other.

(19) In a further step, as illustrated in FIG. 2E, the hydrophilic material 136 may be applied to at least one surface 174 of the element 166. Specifically, the surface 174 may comprise the cover element surface 156 and a test chemical surface 176. Specifically, the hydrophilic layer 162 may be formed on the surface 174. Specifically, the hydrophilic material 136 may be provided such that the hydrophilic material 136 covers the test chemical surface 176 as well. Thus, the surface section 160 may specifically be formed by the cover element surface and the test chemical surface.

(20) In a further step, as shown in FIG. 2F, the cover element 146 and the test chemical 138 are placed onto the substrate 114. Thereby, the element 166 may be placed onto the substrate 114 as one unit 178. Specifically, the foil 124 may be the double-sided adhesive foil 130 and the element 166 may be fixedly attached to the substrate 114 via the double-sided adhesive foil 130. The channel 148 may be formed.

(21) Commonly, the test chemical, specifically the test chemical comprising one or more enzymes, comprises hydrophobic surfaces. This may reduce or limit a transport of the body fluid within the channel 148, specifically to the test chemical 138. Via applying or forming the hydrophilic layer 162 onto the test chemical 138, a transport of the body fluid may be accelerated. Within an experiment, blood was applied as body fluid, specifically blood with a high content of hematocrit, specifically with a portion of 65% of hematocrit. By applying the hydrophilic material 136, the blood having a high hematocrit portion may be transported within the channel 148, specifically to the test chemical 138.

(22) In an experiment, different times were tested which correspond to a period of time how long the hydrophilic material was applied to the surface section 160. At a spray time of 20 seconds, a fill time of 3.4 seconds was reached, by applying a spray time of 40 seconds, a fill time of 4.9 seconds was reached, by applying a spray time of 80 seconds, a fill time of 8.6 seconds was reached. On the contrary, by not applying the hydrophilic material onto the channel surface at all, the sample did not reach the test chemical at all, which virtually corresponds to a fill time of infinity. Additionally, the hydrophilic layer which may be formed on the test chemical surface comprising one or more enzymes may serve as a protection layer at the same time. Specifically, the hydrophobic layer which may be formed as a protection layer may provide a protection against mechanical influences, specifically as the hydrophilic layer may have a flexible, porous structure which may be more stretch-resistant than the test chemical surface.

(23) In FIGS. 3A and 3B, an exemplary embodiment of a test element 110 is shown in a cross-sectional view (FIG. 3A) and in a top view (FIG. 3B). The test element 110 as illustrated in FIGS. 3A and 3B corresponds at least in large parts to the test element as illustrated in FIG. 1E. Thus, reference may be made to the description of FIG. 1E above.

(24) The channel 148 may have a length of 20 mm, a width of 1.5 mm and a height of 70 μm. Further, the substrate 114 and the cover element 146 may be made of polyethylene terephthalate and may have a thickness of 350 μm and 175 μm, respectively. The hydrophilic material may be provided as a solution comprising 2% of polycarbonate urethane and 0.2% of dioctyl sulfosuccinate in tetrahydrofuran.

(25) The hydrophilic material 136 may comprise at least one surfactant such as docusate and/or trisiloxane. The hydrophilic material 136 may further comprise at least one polymer. In an experiment, the surfactant docusate may be applied via spray coating with a spray time of 10 seconds. Thereby, a time how long the body fluid takes from one opening 161 of the channel 148 to the test chemical 138 was determined to 1.7 seconds. A wait time was determined to 2.27 seconds. Thereby, the term “wait time” may refer to a time for the body fluid to overcome the gap between the channel 148 and the test chemical 138. In a further experiment, the surfactant trisiloxane was applied via spray coating with a spray time of 40 seconds. The time for transport within the channel 148 was determined to 1.27 seconds and a wait time was determined to 0.7 seconds. In a further experiment, the surfactant trisiloxane was applied via spray coating with a spray time of 20 seconds. Thereby, the time for transport through the channel was determined to 0.99 seconds, and a wait time was determined to 0.29 seconds. In a further experiment, the surfactant trisiloxane was applied via spray coating with a spray time of 2 seconds. Thereby, a time for transport of the body fluid within the channel 148 was determined to 0.67 seconds. On the contrary, during a reference measurement wherein no surfactant or hydrophilic material was applied, the time of transport of the body fluid within the channel 148 was determined to 4.53 seconds.

(26) Commonly, in order to bridge the gap, an additional aluminum oxide foil may be applied. On the contrary, in the framework of the above described experiments, the hydrophilic material may be applied such that the channel and the test chemical is covered with the hydrophilic material within one step and a transfer of the body fluid to the test chemical may be feasible, thus allowing to considerably reduce the wait time, such as down to a value of 0.29 s.

(27) In further experiments, different fill times have been determined depending on a presence of the hydrophilic material on the channel surface. As used above, the fill time refers to the time required to fill the channel with the body fluid. Without application of a hydrophilic material on the channel surface at all, the fill time was determined as 5.04 seconds. On the contrary, by applying the hydrophilic material, the fill time was determined as 4.78 seconds.

(28) Further, the hydrophilic material may comprise at least one polymer, such as polycarbonate urethane. The polymer may have a surface which corresponds to fleece and may lead to an improvement of a wetting as well as of the fill time.

(29) As illustrated in FIG. 3B, the test element 110 may be manufactured as a roll good 180. Specifically, the adhesive foil 126 (not shown in FIG. 3B) as well as the test chemical 138 and the cover element 146, may be placed on top of the surface 114 and the substrate 114 may provide space for several units of the test chemical 138 such that a plurality of test elements 110 may be generated by cutting the substrate 114 into distinct pieces. Consequently, an assembly comprising the substrate 114, the adhesive foil 126, the test chemical 138 and the cover element 146 may be manufactured as a roll and may be cut into individual test elements 110 thereafter.

(30) In FIGS. 4A to 4B, a further exemplary embodiment of a test element 110 is shown in a cross-sectional view (FIG. 4A) and in a top view (FIG. 4B). The test element 110 as illustrated in FIGS. 4A and 4B corresponds at least in large parts to the test element 110 as illustrated in FIG. 2F. Thus, reference may be made to the description of FIG. 2F above.

(31) The hydrophilic material 136 may comprise Bindzil and Tylose. In an experiment, a fill time or a time for transport of the body fluid within the channel 148 was determined to 1.1 seconds, and the wait time was determined to 0.85 seconds. In FIG. 4B, a top view of the test element 110 is shown. Therein, the test chemical 138 is illustrated. The test chemical 138 and the cover element 146 cover the elongate receptacle 122. A transport of a body fluid 182 within the channel 148 was monitored.

(32) In FIGS. 5A to 5C, a further method for manufacturing a test element for detecting at least one analyte in a body fluid is illustrated. In FIG. 5C, the test element is shown in a perspective view. In FIGS. 5A and 5B, different intermediate products 188 are shown.

(33) In a first step, as shown in FIG. 5A, at least one substrate 190 is provided. The substrate 190 may have at least one elongate receptacle 192. Exemplarily, the elongate receptacle 192 may be stamped into the substrate 190. The substrate 190 may specifically be an embossed foil 193. In a further step, as illustrated in FIG. 5B, at least one test chemical 194 may be placed within the elongate receptacle 192. Before the test chemical 194 is placed into the elongate receptacle 192, at least one foil 196 may be placed into the receptacle. The foil 196 may form a bottom 198 of the elongate receptacle 192. Specifically, the test chemical 194 may be provided as fine cut 200. Further, the test chemical 194 may be either placed into the elongate receptacle 192 or adhered to the elongate receptacle 192, specifically to the foil 196 via at least one adhesive material (not shown).

(34) In a further step, as illustrated in FIG. 5C, at least one hydrophilic element 202 may be placed on the substrate 190. Specifically, the hydrophilic element 202 may be placed on the substrate 190 such that at least one gap 212, as illustrated in FIG. 5B, between the test chemical 194 and at least one surface 114 of the elongate receptacle 192 is filled with the hydrophilic element 202. Exemplarily, the hydrophilic element 102 may be provided as a foil 216. However, other embodiments may be feasible. Further, the hydrophilic element 202 may be coated with at least one hydrophilic layer 218 at least partially. Specifically, the coating of the hydrophilic element 202 may be conducted such that gaps (not shown) within the hydrophilic element 202 may be reduced at least to a large extent.

(35) In FIGS. 6A to 6C, a further exemplary embodiment of a method for manufacturing a test element is illustrated. The test element 186 is illustrated in FIG. 6C in a cross-sectional view, and in FIGS. 6A and 6B different intermediate products 188 are shown. In a first step, as illustrated in FIG. 6A, the substrate 190 is provided. Further, the foil 196 and the test chemical 194 may be placed onto the substrate 190. In a further step, as illustrated in FIG. 6B, the hydrophilic element 202 which may specifically be provided as foil 222 may be placed onto the substrate, thereby covering the test chemical 194 and the foil 196. In a further step, a hydrophilic grid 224 may be placed onto the hydrophilic element 202. In a further step, as illustrated in FIG. 6C, a channel 226 may be formed, specifically via laser welding or gluing.

(36) FIG. 7A shows a relative remission Re in dependence of time t and FIG. 7B shows the corresponding difference of remission ΔRe for different thicknesses of the hydrophilic layer which was applied via blanket coating in this particular embodiment. The data were acquired via a measuring device comprising an UV-LED and a detector and enzymatic reactions were monitored. Curves A correspond to a sample wherein no hydrophilic material was applied. Curves B correspond to a sample, wherein 0.03 g/m.sup.2 of Tylose and 0.72 g/m.sup.2 of Bindzil CC301 were applied leading to a hydrophilic layer with a thickness of 30 μm. Curves C correspond to a sample, wherein 0.05 g/m.sup.2 of Tylose and 1.44 g/m.sup.2 of Bindzil CC301 were applied leading to a hydrophilic layer with a thickness of 60 μm. Curves D correspond to a sample, wherein 0.10 g/m.sup.2 of Tylose and 2.88 g/m.sup.2 of Bindzil CC301 were applied leading to a hydrophilic layer with a thickness of 120 μm. It can be demonstrated that deviations in the kinetics are small. Consequently, applying a hydrophilic layer on the test chemical does not have a significant influence on a performance, i.e. there is no significant influence on kinetics.

LIST OF REFERENCE NUMBERS

(37) 110 test element 112 intermediate product 114 substrate 116 flat substrate 117 flat surface 118 substrate surface 120 direction of extension 122 elongate receptacle 124 foil 126 adhesive foil 128 adhesive surface 130 double-sided adhesive foil 132 further adhesive surface 134 opening 136 hydrophilic material 138 test chemical 139 partition 140 test chemical element 142 test chemical substrate 144 rigid element 146 cover element 148 channel 150 rigid element 152 capillary channel 154 channel surface 156 cover element surface 158 receptacle surface 159 continuous surface section 160 surface section 161 opening 162 hydrophilic layer 164 continuous hydrophilic layer 166 single element 168 support element 170 flat substrate 172 flat surface 174 surface 176 test chemical surface 178 unit 180 roll good 182 body fluid 186 test element 188 intermediate product 190 substrate 192 elongate receptacle 193 embossed foil 194 test chemical 196 foil 198 bottom 200 fine cut 202 hydrophilic element 212 gap 214 surface 216 foil 218 hydrophilic layer 220 gap 222 foil 224 grid 226 channel 228 adhesive surface 230 foil