Heat-curling polymeric needle for safe disposal

Patent metadata

Field	Value
Publication number	US-11400236-B2
Application number	US-201816227517-A
Country	US
Kind code	B2
Filing date	Dec 20, 2018
Priority date	Apr 8, 2013
Publication date	Aug 2, 2022
Grant date	Aug 2, 2022

Abstract

A needle having shaft that forms a tip and a portion proximate to the tip that is formed from a shape memory polymer. The shaft of the needle may be programmed to curl from a straight configuration to a curved configuration upon triggering by heat, thereby moving the sharp tip and providing a non-stick needle for safe and easy disposal.

First claim

What is claimed is:

1. A needle, comprising:
a hollow shaft including a tip and a portion proximate to said tip that is formed from a shape memory polymer having a glass transition temperature above 100 degrees Celsius;
wherein said portion will transition from a temporary configuration that is straight to a permanent configuration that has a curve when said portion is heated to at least said glass transition temperature;
wherein said portion comprises a film formed from a plurality of fibers; and
wherein said curve of said permanent configuration is sufficient to bend said hollow shaft about 180 degrees when said portion is heated to a temperature of 150 degrees Celsius.

2. The needle of claim 1 , wherein said portion has an elastic modulus of about 3.4 GPa at room temperature.

3. The needle of claim 2 , wherein said tip comprises a freeze fractured portion of said hollow shaft.

4. A method of using a needle, comprising the steps of:
providing a needle having a hollow shaft including a tip and a portion proximate to said tip that is formed from a shape memory polymer having a glass transition temperature above 100 degrees Celsius, wherein said portion will transition from a temporary configuration that is straight to a permanent configuration that has a curve when said portion is heated to at least said glass transition temperature, wherein said portion comprises a film formed from a plurality of fibers, and wherein said curve of said permanent configuration is sufficient to bend said hollow shaft about 180 degrees when said portion is heated to a temperature of 150 degrees Celsius;
using said needle to inject a subject;
heating said needle to a temperature of 150 degrees Celsius until said portion transitions from said temporary configuration to said permanent configuration.

5. The method of claim 4 , wherein said portion has an elastic modulus of about 3.4 GPa at room temperature.

6. The method of claim 5 , wherein said tip comprises a freeze fractured portion of said shaft.

7. A method of manufacturing a needle, comprising the steps of:
extruding a needle having a hollow shaft including a tip and a portion proximate to said tip that is formed from a shape memory polymer having a glass transition temperature above 100 degrees Celsius, wherein said portion will transition from a temporary configuration that is straight to a permanent configuration that has a curve when said portion is heated to at least said glass transition temperature, wherein said portion comprises a film formed from a plurality of fibers, and wherein said curve of said permanent configuration is sufficient to bend said hollow shaft about 180 degrees when said portion is heated to a temperature of 150 degrees Celsius;
setting said permanent configuration by heating said needle above a temporary temperature;
programming said temporary configuration by heating said needle under a load to a second temperature that is lower than said temporary temperature; and
freeze fracturing said shaft to form a sharp tip.

8. The method of claim 7 , wherein the step of freeze fracturing said shaft to form a sharp tip comprises cooling said shaft with liquid nitrogen and applying torque.

9. The needle of claim 8 , wherein said portion comprises poly(methyl methacrylate).

Assignees

• Mather Patrick T
• Yang Pine
• Univ Syracuse

Inventors

• Mather Patrick T
• Yang Pine

Classifications

• A61M2005/3212

  Blunting means for the sharp end of the needle · CPC title

• B29K2995/0012

  having particular thermal properties · CPC title

• B29C48/09

  Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels · CPC title

• B29C2948/92704

  Temperature · CPC title

• B29C48/0022

  combined with cutting · CPC title