Microneedle and method for the production thereof

1. Process for producing a microneedle that can be inserted into body tissue in which a needle tip and a capillary collecting channel having a distal inlet for body fluid formed at the needle tip are formed, the process comprising:

a) a preform is prefabricated of a flat material,

b) proximally projecting holding arms are formed on the preform as a holding structure,

c) at least a part of the preform is shaped into a tubular structure so that the collecting channel is at least substantially annularly closed in the cross-section in the area of the tubular structure, and

d) the preform is connected by means of the holding structure to an adapter carrying an analytical test element and/or light guides.

2. Process according to claim 1 , characterized in that a cross-section of the tubular structure is bent annularly while forming a longitudinal continuous closing gap.

3. Process according to claim 1 , characterized in that two outer edges of the preform which face away from one another are abutted and the outer edges are joined at least point-like by joining means or by laser welding spots.

4. Process according to claim 1 , characterized in that the preform is pressed by a form punch into a semi-open mould cavity of a forming tool where the mould cavity defines a partial contour of the tubular structure to be manufactured.

5. Process according to claim 1 , characterized in that the tubular structure is shaped by a closing punch pressed onto the free outer edges of the preform.

6. Process according to claim 1 , characterized in that the preform is pulled through a drawing die, where the drawing die has an opening defining the contour of the tubular structure.

7. Process according to claim 1 , characterized in that the preform is formed from a plastic foil and is converted into the tubular structure by thermoforming.

8. Process according to claim 1 , characterized in that a plurality of preforms are prestructured as a contiguous composite preferably by etching or laser cutting.

9. Process according to claim 1 , characterized in that the collecting channel is connected at a proximal outlet to an analytical test element that reacts to a component of the body fluid.

10. Process according to claim 1 , characterized in that a spreading element which distributes the collected body fluid two-dimensionally is attached to a proximal outlet of the collecting channel.

11. Process according to claim 1 , characterized in that the preform is connected by means of the holding structure to the adapter carrying the analytical test element and/or light guides by means of a plug connection.

12. Process according to claim 1 , characterized in that the tubular structure is provided with an in particular elliptical proximal opening that deviates from a circular shape.

13. Process according to claim 1 , characterized in that the tubular structure is formed with a polygonal contour in particular by folding lines in the preform.

14. Process according to claim 1 , characterized in that the needle tip is formed on the preform by etching, cutting or grinding and/or made after formation of the tubular structure.

15. Process according to claim 1 , characterized in that a hydrophilic layer is applied at least to the inner side of the tubular structure.

16. Process according to claim 1 , characterized in that collecting channel is formed as a capillary flow path between the distal inlet and a proximal outlet so that body fluid is transported by capillary action from the inlet to the outlet.

17. Process according to claim 1 , characterized in that the collecting channel is formed with a diameter in the range between 50 and 500 μm, preferably between 100 and 200 μm.

18. A process for producing a microneedle that can be inserted into body tissue in which a needle tip and a capillary collecting channel having a distal inlet for body fluid formed at the needle tip are formed, the process comprising:

a) a preform is prefabricated of a flat material,

b) a pair of proximally projecting holding arms are formed on the preform as a holding structure,

c) at least a part of the preform is shaped into a tubular structure so that the collecting channel is at least substantially annularly closed in the cross-section in the area of the tubular structure, and

d) the preform is connected by means of the holding structure inserted into a pair of lateral receiving grooves on an adapter carrying an analytical test element and/or light guides.

19. A process for producing a microneedle that can be inserted into body tissue in which a needle tip and a capillary collecting channel having a distal inlet for body fluid formed at the needle tip are formed, the process comprising:

a) a preform is prefabricated of a flat material,

b) a first proximally projecting holding arm and a second proximally projecting holding arm are formed on the preform as a holding structure, wherein the first proximally projecting holding arm is substantially parallel to the second proximally projecting holding arm,

c) at least a part of the preform is shaped into a tubular structure so that the collecting channel is at least substantially annularly closed in the cross-section in the area of the tubular structure, and

d) the preform is connected by means of the holding structure to an adapter carrying an analytical test element and/or light guides.