Introduction

The stability of medicine in the blood stream is another challenge being tackled in the biomedical engineering community. The first challenge is the result of the composition of the blood. 55% of blood is plasma and 95% of plasma is water. Therefore, medicine delivered through the vasculature will be primarily interacting with a water-based solution. However, many of the medicine are hydrophobic molecules and are quite insoluble in the blood. Also, many of the molecules are actively cleared out of the blood stream and only very few reach their destination. The result of this is a large dosage is required to achieve an effective concentration in the tumor to treat the cancer.

In addition to directing the destination of the therapeutics, methods are also being investigated to “protect” the drugs in the blood stream. The ultimate goal is to increase the half-life of the medicine in the blood stream to allow sufficient amounts to reach the tumor.

Solutions

Various methods have been devised to combat this problem. One such method is the encapsulation of the medicine inside a carrier. This carrier will not only increase the solubility of the drug, but also help protect it from digestion and clearance from the body. Different strategies of encapsulation have also been developed using a wide array of molecule to serve as the carrier.

Click on the pictures below to find out more about each method.