Medicine solubility determines success of smart drugs

The encapsulation of medicines into state-of-the-art carriers is determined by their solubility, researchers from Utrecht University and Eindhoven University of Technology have revealed. This provides more control over the postponed release of medicine in a patient's body, and opens up the possibility of developing other smart drugs. The work is featured on the cover of the scientific journal Langmuir.

Active in the right part of the body

Targeted therapy is one of the most important forms of cancer therapy. Attached to a transport material, medicinal particles are brought into the blood channel and do not become active until they are in the right part of the body. This results in much less side effects for the patient, because healthy, normally dividing cells are being left in peace. A transport method for this type of therapy is a so-called micelle, a particle with a water loving (hydrophilic) and a water repellent (hydrophobic) part. In spite of being a successful drug transport method, until now it hadn't been proved how this postponed release of a medicine by the micelle really works.

Near the core or between the tentacles

The Utrecht PhD candidate Álvaro González García together with his colleagues from Eindhoven found out how drugs distribute in the micelles that are currently in use. González García: "It all turns out to come down to the solubility of the drug. In blood, the hydrophobic part of a micelle turns to the inside, while the solvent-loving part turns outside. Consequently, a water repellent core is surrounded by water loving tentacles." Their solubility makes some medicine concentrate in the center of the hydrophobic core, which causes a delayed release. Other medicine reside in between the hydrophilic tentacles of the micelle, and consequently are released earlier.

Fundamental knowledge for more controlled application

The researchers think that their insights could influence the combination of drug and transport packages. González García: "We now have fundamental knowledge on a medical application that is under development already for years. Our results pave the way towards development of other smart drugs."

More information:
“Controlling the spatial distribution of solubilized compounds within copolymer micelles”, Alessandro Ianiro, Álvaro González García, Stefan Wijker, Joseph P. Patterson, A. Catarina C. Esteves, en Remco Tuinier Langmuir DOI:10.1021/acs.langmuir.9b00180

Provided by Utrecht University Faculty of Science