I found out for the first time ever that the nanoparticles I use to ferry drugs around the body are able to recirculate through a special transport system. This means that if you take these nanoparticles in the form of a pill, they will go into your gut, dissolve into the bile salts (the bile is what your body makes to help you digest fat), cross the gut wall together with the bile into your blood stream, travel around your body to your liver and then be transported from the liver to your gall bladder.
Once there, they can be squirted back into the gut to have another go at travelling around your body in your blood. This gives the drugs being carried by the nanoparticles even more of a chance to get where they’re needed to do your body good.
I drew a picture to demonstrate this: the green solid lines represent the nanoparticles in the blood, and the green dashed lines represent the nanoparticles in the intestines.