Scientists create “lighting switches” for precise drug delivery

In the development that can alter the development of drugs in the body, researchers at the University of Geneva have created a system that uses light to accurately activate when and where drugs are. Advances published in natural communications may lead to more effective treatments with fewer side effects.

The team developed a method to modify drug molecules so that they remain inactive until exposed to specific pulses of light and then trapped inside target cells. This precise targeting may greatly reduce the systemic effects that make many current drugs cause adverse side effects throughout the body.

A new method of drug delivery

“It all starts with this methodological problem,” explains Monica Gotta, professor in the Department of Cell Physiology and Metabolism of Unige School of Medicine. The team initially tried to control a protein involved in cell division to better understand its role in organism development.

Chemical locks and keys

The researchers modified a molecule that inhibits PLK1 by adding two photosensitive components. One ingredient prevents the drug from working until it is activated by light, while the other acts as a molecular anchor, confining the activated drug to specific cells.

“After a complex process, we were able to block the active site of the inhibitor with coumarin derivatives, a compound that is naturally occurring in certain plants. This coumarin can then be removed with a simple light pulse white.

Accuracy through light

The effectiveness of this system was demonstrated in both single cell and three-dimensional cell cultures. When the researchers applied a brief pulse of light in a specific area, only the cells in that area were affected by the drug, while the adjacent cells remained the same.

This level of control may be particularly valuable for current treatments that cause serious side effects. In Switzerland alone, thousands of people suffer from severe drug-related side effects every year.

Future applications

“We hope that our tools will be widely used to better understand the functions of biological organisms and, in the long run, develop location-specific treatments.”

This technology may be adapted to many different types of drugs. Future applications may include the use of simple lasers to precisely activate treatments while requiring a healthy tissue, which may alter treatments for diseases such as skin cancer and other local diseases.

Collaborative achievements

The study represents a successful collaboration between biologists and chemists. Nicolas Winsinger, a professor in the Unige Department of Organic Chemistry, explained that the team was able to “activate and anchor inhibitors with the same pulse of light”, creating a dual mechanism to precisely control the activity of the drug.

Although the system can currently use visible light, which can penetrate only short distances to tissue, researchers believe that future developments may use different wavelengths or two-light activations for deeper tissue penetration, thus amplifying Potential applications of this approach.