New potential These light-controlled patches release active ingredients in a controlled manner

Intelligent patch with light switch to revolutionize medication

Not every drug is suitable to be taken orally or via a syringe. At the same time, our largest organ often remains unused. The skin provides the largest permeable area to absorb drugs from remedies. Researchers from Switzerland are currently developing a novel patch that delivers active ingredients to the skin via integrated containers. This charge is controlled by the light.

Smallest nanocontainers are integrated in the intelligent patch, which can be filled with a variety of active ingredients. The active ingredients can be dispensed targeted by light signals. This opens up completely new methods in drug therapy. The light-controlled patch is currently being developed by researchers from Empa and the University of Friborg. A paper on this topic has recently been published in the Journal of the American Chemical Society.

A new patch, which is currently under development, can incorporate multiple drugs through integrated nanoparticles, which are released via a specific light signal. (Image: ChristArt / fotolia.com)

Medicine that goes through the skin

Some active ingredients can even be applied as a patch well over the skin, such as nicotine replacement, certain painkillers or contraceptives. This repertoire could greatly expand with the new patch, as reported by Empa researchers in St. Gallen and the Adolphe Merkle Institute of the University of Friborg. With the new technology, the dosage of active ingredients could be controlled precisely via light signals.

How does the new plaster system work?

To precisely control the active ingredients in the patch, the research team has developed a molecular light switch that is inspired by nature. "Our light switch operates on the principle of the retina in the human eye," explains Luciano Boesel from the Empa laboratory for biomimetic membranes and textiles in a press release on the study results. Like the natural dyes in the eye, these synthetic photochromes could also be activated by light. These switches were incorporated into microscopic polymer nanospheres that then release the content of the drug via a light signal.

High tech plaster

A certain wavelength of the light causes a structural change in the integrated nanoreactors. The shell becomes permeable as a result and the active ingredients contained can escape. At a different wavelength, this reaction stops within seconds and the drug is not released.

A portable medication reservoir

The new patch can serve as a portable medication reservoir that delivers precise drug delivery whenever needed. "It is possible to use light switches for the entire spectrum between 450 and 700 nanometers wavelength, ie for colored light from blue to red," reports Boesel. This leaves a margin for the controlled delivery of multiple drugs to complex reaction cascades in a single patch.

Further optimization required

With the support of the National Fund and the National Center of Competence Research for Bio-Inspired Materials, the team is currently working to further optimize the light-sensitive patch. "First, we will examine the precisely controllable delivery of substances that are already approved for application through the skin, such as certain painkillers," summarizes Boesel. In the future, however, many more treatments with the plaster are conceivable. (Vb)