Microdeposition system for a biosensor
View Patent ↗A microdeposition pin having a contact surface with at least one concave edge for creating microarrays and the like. The microdeposition pin may be used either alone or with a plurality of microdeposition pins in conjunction with a holder. The concave edge of the pin is especially adapted for helping to control the spreading of a deposited material. By selectively controlling the spread of the reagent composition from the microdeposition pin, the flow of the reagent composition from the deposition target area may be reduced. Sensor strips having raised substrate features with limited or no spreading of the reagent composition beyond the target area are disclosed.
1. A microdeposition pin, comprising:
a shaft terminating in a head, the head having:
a base,
a contact surface including at least two convex and at least two concave edges,
the cross-section of the contact surface having a maximum diameter between two convex edges from about 0.25 mm to about 3 mm, having a minimum distance between two concave edges from about 0.1 mm to about 1.5 mm, and having a ratio of the maximum diameter to the minimum distance of from 7.5 to 0.33, and
side surfaces connecting the base to the contact surface and including a concave side wall.
2. The pin of claim 1 , wherein said contact surface further includes a flat edge.
3. The pin of claim 1 , wherein said side surfaces include a first side wall that is approximately perpendicular to said contact surface.
4. The pin of claim 1 , wherein said side surfaces include a first side wall that is angled relative to said contact surface of the pin.
5. The pin of claim 1 , wherein said side surfaces include a concave side wall intersecting said contact surface to form one of the concave edges, wherein said concave side wall extends substantially the length of said head.
6. The pin of claim 1 , wherein said side surfaces include a concave side wall intersecting said contact surface to form one of the concave edges, wherein said concave side wall is tapered along a length of said head.
7. The pin of claim 1 , wherein said head includes a channel therein terminating at an aperture disposed at said contact surface.
8. The pin of claim 1 , further comprising a collar remote from said head of said pin, said collar adapted for affixing said pin to a holder.
9. The pin of claim 1 , the cross-section of the contact surface having the maximum diameter from about 2 mm to about 3 mm, the minimum distance from about 1 mm to about 1.5 mm, and a maximum arc distance from about 1.3 mm to about 1.4 mm, where a radius defines the arc of at least one of the concave edges, and the radius has a length from about 3 mm to about 4 mm.
10. An apparatus for the deposition of a reagent composition, the apparatus comprising:
at least one microdeposition pin comprising:
a shaft terminating in a head, the head having:
a base;
a contact surface including at least two convex and at least two concave edges, where the cross-section of the contact surface has a maximum diameter between two convex edges from about 0.25 mm to about 3 mm, has a minimum distance between two concave edges from about 0.1 mm to about 1.5 mm, and has a ratio of the maximum diameter to the minimum distance of from 7.5 to 0.33;
side surfaces connecting the base and the contact surface and including a concave side wall; and
a holder for grasping said at least one microdeposition pin such that said contact surface is remote from said holder.
11. A method of forming a reagent composition footprint, comprising:
depositing an amount of the reagent composition onto a contact surface of a pin, said contact surface having at least two convex edges and at least two concave edges, where the cross-section of the contact surface has a maximum diameter between two convex edges from about 0.25 mm to about 3 mm, has a minimum distance between two concave edges from about 0.1 mm to about 1.5 mm, and has a ratio of the maximum diameter to the minimum distance from 7.5 to 0.33; and
engaging said contact surface of said pin with a substrate to form a reagent composition deposition on the substrate,
the reagent composition deposition comprising a footprint having at least one substantially straight edge.
12. The apparatus of claim 10 , wherein said at least one microdeposition pin includes a plurality of microdeposition pins, wherein each pin includes a contact surface having at least two convex and at least two concave edges; where the cross-section of the contact surface of each pin has a maximum diameter between two convex edges from about 0.25 mm to about 3 mm, has a minimum distance between two concave edges from about 0.1 mm to about 1.5 mm, and has a ratio of the maximum diameter to the minimum distance of from 7.5 to 0.33.
13. The apparatus of claim 12 , where the cross-section of the contact surface of each pin has the maximum diameter from about 2 mm to about 3 mm, the minimum distance from about 1 mm to about 1.5 mm, and a maximum arc distance from about 1.3 mm to about 1.4 mm, where a radius defines the arc of at least one of the concave edges, and the radius has a length from about 3 mm to about 4 mm.
14. The apparatus of claim 10 , where the cross-section of the contact surface has the maximum diameter from about 2 mm to about 3 mm, the minimum distance from about 1 mm to about 1.5 mm, and a maximum arc distance from about 1.3 mm to about 1.4 mm, where a radius defines the arc of at least one of the concave edges, and the radius has a length from about 3 mm to about 4 mm.
15. The method of claim 11 , where the reagent composition deposition comprises a footprint having at least two substantially straight edges.
16. The method of claim 15 , where the reagent composition deposition is rectangular in shape.
17. The method of claim 15 , where the deposition has a length of from about 0.15 mm to about 3.2 mm, and a width of from about 0.2 mm to about 1.2 mm.
18. The method of claim 15 , where the deposition has a thickness of about 1 μm to about 2 μm.
19. A microdeposition pin, comprising:
a shaft terminating in a head, the head having:
a base;
a contact surface including:
a first convex edge;
an opposing second convex edge;
a first concave edge connecting the first and second convex edges at respective first ends thereof;
an opposing second concave edge connecting the first and second convex edges at respective second ends thereof; and
side surfaces connecting the base to the contact surface and including a concave side wall that forms one of the first and second concave edges,
wherein the cross-section of the contact surface includes:
a maximum diameter between the first and second convex edges from about 0.25 mm to about 3 mm; and
a minimum distance between the first and second concave edges from about 0.1 mm to about 1.5 mm.
20. The pin of claim 19 , wherein the concave side wall is approximately perpendicular to the contact surface.
21. The pin of claim 19 , wherein the concave side wall is tapered along a length of the head.
22. The pin of claim 19 , wherein the head includes a channel therein terminating at an aperture disposed at the contact surface.
23. The pin of claim 19 , further comprising a collar remote from the head of the pin, the collar adapted for affixing the pin to a holder.
24. The pin of claim 19 , the cross-section of the contact surface having the maximum diameter from about 2 mm to about 3 mm, the minimum distance from about 1 mm to about 1.5 mm, and a maximum arc distance from about 1.3 mm to about 1.4 mm, where a radius defines the arc of at least one of the first and second concave edges, and the radius has a length from about 3 mm to about 4 mm.