Self-Sealing Needles for Preventing Blood Loss After Injection

For most of us, a visit to the doctor for an injection is a harmless yet fear-filled and painful process. But for patients with hemophilia, a disorder where the body’s ability to make blood clots is impaired, injections could be life threatening. Researchers from the Korea Advanced Institute of Science and Technology and the University of Science and Technology in Republic of Korea have developed a thin, biodegradable polymer coating that can ‘plug’ an injection site.

The polymer is made from a naturally derived material called chitosan, which is found in the shells of crustaceans. The solid coating on the needle becomes a tougher, stronger gel on encountering blood in our vessels, and can successfully prevent bleeding.

To confirm the functionality of these coatings, the researchers compared regular needles and the modified ones in mice with hemophilia. While mice injected with regular needles all died due to excessive bleeding, a 100% survival rate was observed in mice injected with the coated needles.

From the study abstract in Nature Materials:

Bleeding is largely unavoidable following syringe needle puncture of biological tissues and, while inconvenient, this typically causes little or no harm in healthy individuals. However, there are certain circumstances where syringe injections can have more significant side effects, such as uncontrolled bleeding in those with haemophilia, coagulopathy, or the transmission of infectious diseases through contaminated blood. Herein, we present a haemostatic hypodermic needle able to prevent bleeding following tissue puncture. The surface of the needle is coated with partially crosslinked catechol-functionalized chitosan that undergoes a solid-to-gel phase transition in situ to seal punctured tissues. Testing the capabilities of these haemostatic needles, we report complete prevention of blood loss following intravenous and intramuscular injections in animal models, and 100% survival in haemophiliac mice following syringe puncture of the jugular vein. Such self-sealing haemostatic needles and adhesive coatings may therefore help to prevent complications associated with bleeding in more clinical settings.

Paper in Nature Materials: Complete prevention of blood loss with self-sealing haemostatic needles…