Research advances towards the design of drug delivery micro-vehicles

Dr. Marco Soto Arriaza, a researcher at the Faculty of Medicine and Science, uses tiny synthetic “bubbles” to study the flow and transport of molecules through their membrane: a key aspect for developing systems capable of administering drugs -or other substances- directly into a cell.

All cells have a membrane that protects it and separates its interior from its exterior, regulating the passage of materials that enter and leave it: a basic and fundamental dynamics for the functioning of life.

Recently joined the Faculty of Medicine and Science, Dr. Marco Soto Arriaza explores the dynamics of transport into and out of this membranous barrier, using synthetic models called liposomes: small spherical vesicles composed of a membrane enclosing a watery interior.

As a sort of microscopic bubble, they are widely used to transport and deliver drugs and nutrients. Thus, Dr. Soto Arriaza explains that, in the first stage of his line of research, he dedicated himself to “studying different types of molecules of biological importance and how they interact with membrane models; that is, to understand how they behave, how they are inserted, and what is the effect of the insertion in the models”.

After characterizing these systemsthe subsequent focus of his work was to stabilize them in such a way that they were capable of encapsulating or enclosing substances, such as drugs or molecules of interest, and transporting them while remaining stable over time. This, considering aspects such as the route of entry of the drug, whether it is injected or ingested, among other factors.

“We were looking for polymers that would have an effect so that the systems remain longer in the circulatory system, managing to increase their stability and not lose their shape,” he explains. Likewise, differences were found in the speed with which the encapsulated materials are released; namely, Depending on the composition, rigidity and permeability of these miniature transport systems, it is possible to delay the release of the enclosed drug.

health applications

One of the main applications to which this work points is the encapsulation, transport and controlled release of antineoplastic drugs -such as doxorubicin- that attack and eliminate tumor cells (as well as enzymes, molecules of food importance, probiotics, etc.).

For this end, Research is moving towards more sophisticated vehicles. That is, systems that are not only stable over time and controlled release, but that do so in a specific type of cell, such as tumor cells, and not in another.

This is very relevant considering that drugs such as those used in chemotherapy are necessarily toxic, since strictly speaking they must “kill” cancer cells, however, they are not selective and incidentally also affect healthy tissues. Along with low drug efficacy, this implies significant side effects for patients, which may be permanent.

Dr. Soto Arriaza explains that the use of liposomes as transport systems brings with it a wide range of opportunities. “The systems are very versatile and transversal with respect to the objective that you want to achieve,” he points out. Thus, among other projects, he is beginning to work with photosensitive molecules that, when irradiated with light, produce oxidative damage in cells, which opens the door to other mechanisms to attack tumor cells, as well as bacteria of food origin, among other possibilities.