Nanoparticles That Carry Drugs: Nanopills | Insulin Pill is On The Way
How Does A Normal Pill Work?
Pills actually need to get access to the bloodstream to deliver the right payload for any problems in the human body. Not all medicines could be taken as a capsule or a tablet. The medicine/drug when administered through a tablet, it gets absorbed by the walls of the small intestine and the stomach, to get into the bloodstream. Now it just have no idea where to act (e.g. Aspirin) so it just goes everywhere along with the blood and finally finds its delivery address, the place where it has to deliver the drug and fix it. The drug, then binds with the receptor (sort of a security guard for the cells) with the small proteins they contain (more like an Identification card into the cell). The drug then fixes the cells.
The Insulin Problem
Well, not all drugs can be taken as a pill/tablet/capsule. Pills are only taken when the molecules to be delivered are non-reactive to the acids in the stomach and the drug molecules are small enough to penetrate the intestinal layer to enter the bloodstream. Insulin, which reacts with these acids are also slightly large molecules. And that’s the reason why the insulin hormone is administered through an injection right into the bloodstream.
Nanopills might allow us to administer Insulin and other drugs that are also delivered intravenously(IV). Researchers from Brigham and Women’s Hospital and MIT have figured out a way to deliver Insulin with the help of pills coated with nanoparticles.
How Nanopills Work?
As I’ve mentioned above, the pills needs to get through the epithelial cells to get into the bloodstream. These cells usually form a barrier that is quite hard enough to get through. This barrier is also known as the tight zones. Researchers somehow tried to disrupt this layer often as a forced entry. But as there were risks involved, say bacteria use this forced entry to tag along with the nanoparticles, they sought a better way for a passive entry.
Recently, they figured out a way to infiltrate the ‘tight zone’ passively by adapting the way how a baby gets its immunity from its mother’s milk absorbing the antibodies from the milk. The intestinal lining cells have a receptor called neonatal Fc receptor (Laymen term: A Lock!). The FcRn binds with the Fc protein IgG (Laymen term: A Key!). The researchers coated the nanoparticle with these Fc proteins and found a way to transport the insulin and other blocks of payloads successfully through the epithelial cells into the bloodstream. This was successfully demonstrated by reducing the sugar level of a mouse by delivering the insulin orally with a nanopill.
While the pills are now being tested on animals, they are also tested for other barrier penetrations like the blood brain layer and the mucosa layer in the lungs. Hope the research team comes up with the successful insulin pills and adds some smoothies into the life of diabetics. Chemo pills are on the way too.
This post was first published on November 29, 2013.