BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to hypodermic needles and, more particularly, to a needle having a curlable tip formed from a shape memory polymer.

2. Description of the Related Art

Improper and unsafe needle-syringe disposal is a worldwide healthcare issue. It has been well documented especially in developing countries which cause tens of millions of hepatitis and HIV infections each year. The conventional steel needle requires high temperature for incineration and will generate a large amount of waste. Even after disabling the needles, they are still sharp hazards and potentially dangerous for the recycling workers. Auto-disable needle-syringes have been developed in recent years to solve the problem of reusing, most of these devices worked by preventing the syringes plunger from being withdrawn after injection. These needles are complicated designs that involve multiple actuating parts, including sleeves and/or springs. Thus, the needle disposal and recycling problem has not yet been solved.

BRIEF SUMMARY OF THE INVENTION

The present invention comprises a needle having a tip formed from a shape memory polymer (SMP). SMPs are a class of stimuli-responsive materials that can undergo a shape change based on specific stimuli or conditions. SMPs have been widely used in biomedical devices such as deployable stents and aneurysm occlusion devices. A conventional steel needle is replaced with a polymer needle having a programmable SMP, thus providing a disabling process that is easy, fast and safe. In a preferred embodiment, the needle tip will curl and become non-stick upon triggering by heat, thereby transitioning to a curled and non-stick shape for safe and easy disposal. There present invention may be manufactured from a commercially available polymer that features good shape memory characteristics, such as high molecular weight poly(methyl methacrylate) (PMMA).

