When type 2 diabetes has progressed to an advanced stage, the pancreas is unable to make adequate insulin. Doctors typically advise daily insulin shots at this period to control blood sugar levels.

But according to research, one of the biggest obstacles preventing people with type 2 diabetes from using insulin is a fear of needles.

Robert Langer, a professor at the Koch Center for Integrative Cancer Research, Massachusetts Institute of Technology (MIT), Cambridge, and his colleagues want to make insulin treatment more tolerable by fundamentally altering the way it is administered.

Using microneedles to deliver the drug

The group developed a brand-new pill formulation that consists of a biodegradable capsule that also houses an insulin microneedle. The stomach wall receives a direct injection of insulin when the pill is swallowed. The researchers think that this method of medicine delivery will be painless because the stomach lining lacks any pain receptors.

Scientists first created millimeter-sized microneedles to pierce the skin without inflicting pain. The microneedle used in this investigation had two parts: a compressed insulin-filled tip that pierces the stomach wall and a biodegradable shaft that secures the tip.

The needle is attached to a compressed spring and a disc made of sugar within the capsule. When the capsule is ingested, the sugar disc dissolves. The microneedle can then inject into the stomach wall after the spring is released as a result of doing this.

What prevents the microneedle from shooting off in the incorrect direction and missing the stomach wall, despite the deceptively simple appearance of this mechanism?

“As soon as you take it, you want the system to self-right so that you can ensure contact with the tissue,” says Giovanni Traverso, an assistant professor at Brigham and Women’s Hospital, Harvard Medical School, Boston, MA.

Taking inspiration from tortoise shells

The answer came from an unexpected source. The leopard tortoise, which is indigenous to Eastern and Southern Africa and has a high-domed shell, is an expert at self-righting.

The researchers employed computer modeling to create the capsule, using design cues from the shape of the tortoise shell. The capsule’s ability to self-right itself ensures that the needle makes contact with the stomach wall regardless of how it enters the stomach.

Alex Abramson, a doctoral student at MIT and the study’s first author, says that it is crucial to have the needle in direct contact with the tissue when it is injected. Also, the device would not change from its preferred orientation if a person moved, or their stomach grumbled.

Insulin enters the bloodstream after the microneedle tip dissolves after being injected into the stomach wall. This process took around an hour in the current investigation, although the researchers can somewhat regulate the rate by how they prepare the microneedle.

The researchers have demonstrated that they can use this technique to give doses as high as 5 milligrams thus far. The capsule itself does not have any negative effects while it travels through the digestive system.

The capsule system is still being developed further. The research team is optimistic that this new design will put an end to a number of medications that can only be administered intravenously at this time.

Reference:

Diabetes: Could a pill replace insulin injections? (no date) Medical News Today. MediLexicon International. Available at: https://www.medicalnewstoday.com/articles/324389 (Accessed: March 9, 2023).