Needle shields to minimize needle corrosion

Abstract

Provided herein is a needle shield for use in a pre-filled or pre-fillable syringe. The syringe includes a syringe assembly having a barrel with a barrel end portion at its terminal end, a needle having a proximal end fixedly inserted into the barrel end portion, and a needle shield being mounted to the barrel via the barrel end portion and positioned on the needle. The plunger is received within the chamber of the barrel and is axially movable within it. The needle shield comprises an adaptable material that at least partially forms a hollow cavity inside it, the hollow cavity comprising a needle housing where the needle is positioned when the needle shield is mounted to the barrel, and the walls partially forming the needle housing portion have an angle α of 8° to 90° with respect to the longitudinal axis of the needle shield.

Claims

1. A pre-filled or pre-fillable syringe, wherein the syringe is Syringe assembly, A barrel having a barrel end and a barrel base end, defining a chamber, wherein the barrel includes a barrel end portion at the barrel end. A needle having a needle tip at the terminal end and a base end that is fixedly inserted into the barrel end portion, and A needle shield, which is placed on the barrel via the barrel end portion and positioned on the needle, Syringe assemblies, and The barrel comprises a plunger that is received within the chamber and is movable axially inside it, In a syringe, the needle shield comprises an adaptable material that at least partially defines a hollow cavity inside, and the hollow cavity includes a needle receiving portion in which the needle is positioned when the needle shield is placed on the barrel, A syringe characterized in that the wall forming the inner surface portion of the needle receiving portion has an angle α of 8° to 90° with respect to the longitudinal axis of the needle shield.

2. The angle α is defined as follows: [Math 1] The syringe according to claim 1, wherein W is the width of the hollow cavity at the open base end of the needle receiving portion, w is the width of the tip portion of the needle receiving portion, D is the length of the needle receiving portion, and d is the length of the small diameter tip portion.

3. Length D is constrained as follows: [Math 2] The syringe according to claim 2, wherein L is the length of the needle between the needle tip and the open base end of the needle shield cavity, and l is the length of the bevel of the needle at the needle tip.

4. The syringe according to claim 2 or 3, wherein w = 0.4 mm and is configured to accept a needle of 25G, 27G, or 29G.

5. The syringe according to any one of claims 1 to 4, wherein the angle α is preferably 9° to 90°, and more preferably 9.5° to 90°.

6. The syringe according to any one of claims 1 to 5, wherein friction or wiping between the needle and the wall partially forming the inner surface of the needle receiving portion decreases as the value of the angle α increases.

7. The syringe according to any one of claims 1 to 6, wherein the needle receiving portion comprises an open proximal end and a terminal end, and the wall of the needle receiving portion is tapered inward from the open proximal end to the terminal end.

8. The syringe according to claim 7, wherein the tip portion is positioned at the terminal end of the needle receiving portion, and the tip portion has an inner diameter larger than the outer diameter of the needle.

9. The syringe according to claim 8, wherein the tip portion of the needle receiving portion has a certain inner diameter.

10. The syringe according to claim 8 or 9, wherein when the needle shield is placed on the barrel, the tip portion of the needle receiving portion accommodates the needle tip portion.

11. The syringe according to any one of claims 1 to 10, wherein the hollow cavity includes a barrel end storage portion configured to receive the barrel end portion.

12. The syringe according to any one of claims 1 to 11, wherein the adaptable material includes rubber.

13. The syringe according to any one of claims 1 to 12, wherein the needle shield comprises a rigid outer surface positioned around the adaptable material.

Images