30-Sep-2020 - Technische Universität München

Secure nano-carrier delivers medications directly to cells

Nanoparticles with synthetic DNA can control release of drugs

Medications often have unwanted side-effects. One reason is that they reach not only the unhealthy cells for which they are intended, but also reach and have an impact on healthy cells. Researchers at the Technical University of Munich (TUM), working together with the KTH Royal Institute of Technology in Stockholm, have developed a stable nano-carrier for medications. A special mechanism makes sure the drugs are only released in diseased cells.

The human body is made up of billions of cells. In the case of cancer, the genome of several of these cells is changed pathologically so that the cells divide in an uncontrolled manner. The cause of virus infections is also found within the affected cells. During chemotherapy for example, drugs are used to try to destroy these cells. However, the therapy impacts the entire body, damaging healthy cells as well and resulting in side effects which are sometimes quite serious.

A team of researchers led by Prof. Oliver Lieleg, Professor of Biomechanics and a member of the TUM Munich School of BioEngineering, and Prof. Thomas Crouzier of the KTH has developed a transport system which releases the active agents of medications in affected cells only. "The drug carriers are accepted by all the cells," Lieleg explains. "But only the diseased cells should be able to trigger the release of the active agent."

Synthetic DNA keeps the drug carriers closed

The scientists have now shown that the mechanism functions in tumor model systems based on cell cultures. First they packaged the active ingredients. For this purpose, they used so-called mucins, the main ingredient of the mucus found for example on the mucus membranes of the mouth, stomach and intestines. Mucins consist of a protein background to which sugar molecules are docked. "Since mucins occur naturally in the body, opened mucin particles can later be broken down by the cells," Lieleg says.

Another important part of the package also occurs naturally in the body: deoxyribonucleic acid (DNA), the carrier of our genetic information. The researchers synthetically created DNA structures with the properties they desired and chemically bonded these structures to the mucins. If glycerol is now added to the solution containing the mucin DNA molecules and the active ingredient, the solubility of the mucins decreases, they fold up and enclose the active agent. The DNA strands bond to one another and thus stabilize the structure so that the mucins can no longer unfold themselves.

The lock to the key

The DNA-stabilized particles can only be opened by the right "key" in order to once again release the encapsulated active agent molecules. Here the researchers use what are called microRNA molecules. RNA or ribonucleic acid has a structure very similar to that of DNA and plays a major role in the body's synthesis of proteins; it can also regulate other cell processes.

"Cancer cells contain microRNA strands whose structure we know precisely," explains Ceren Kimna, lead author of the study. "In order to use them as keys, we modified the lock accordingly by meticulously designing the synthetic DNA strands which stabilize our medication carrier particles." The DNA strands are structured in such a way that the microRNA can bind to them and as a result break down the existing bonds which are stabilizing the structure. The synthetic DNA strands in the particles can also be adapted to microRNA structures which occur with other diseases such as diabetes or hepatitis.

The clinical application of the new mechanism has not yet been tested; additional laboratory investigations with more complex tumor model systems are necessary first. The researchers also plan to investigate further modifying this mechanism to release active agents in order to improve existing cancer therapies.

Facts, background information, dossiers

  • drug delivery
  • drug carriers

More about TUM

  • News

    Bright, stable, and easy to recycle lighting

    A low-cost and easy-to-manufacture lighting technology can be made with light-emitting electrochemical cells. Such cells are thin-film electronic and ionic devices that generate light after a low voltage is applied. Researchers at the Technical University of Munich (TUM) and the University ... more

    Light may increase performance of fuel cells and lithium-ion batteries

    Lithium-ion batteries, fuel cells and many other devices depend on the high mobility of ions in order to work properly. But there a large number of obstacles to such mobility. A research team led by Jennifer L. M. Rupp of the Technical University of Munich (TUM) and Harry L. Tuller of the M ... more

    Targeted enzymes destroy virus RNA

    A research team led by the Technical University of Munich (TUM) has successfully used specific enzymes to destroy the genetic information of SARS-CoV-2 directly after the virus penetrates the cell. The findings could serve as the basis for a therapy to treat COVID-19. Our genome contains bu ... more

  • q&more articles

    Vital wheat gluten, a protein with potential

    For almost every one of the 17 goals that the 2030 Agenda for Sustainable Development sets out, food and its value chain plays an important role [1]. With this agenda, the United Nations has created a global framework for action that addresses all social players. more

    Biobased raw material flows of the future

    Anthropogenic climate change and the rising world population, in combination with increasing urbanization, poses global challenges to our societies that can only be solved by technological advancement. The direct biotechnological use of greenhouse gases, including residual biomass flows fro ... more

    Taste and aroma boost in the mouth

    The food trend towards healthy snacks is continuing. Snacks made from freeze-dried fruit meet consumer expectations of modern and high-quality food. However, freeze drying of whole fruits requires long drying times and substantially reduces sensorial quality, which is unappealing to consumers. more

  • Authors

    Prof. Dr. Thomas Becker

    Thomas Becker, born in 1965, studied Technology and Biotechnology of Food at the Technical University of Munich (TUM). He then worked as a project engineer at the company Geo-Konzept from 1992 to 1993. In 1995, he received his PhD from the TUM. From 1996 to 2004 he was Deputy Head of Depart ... more

    Monika C. Wehrli

    Monika Wehrli, born in 1994, graduated from the ETH Zurich with a major in food process engineering. Since 2018 she has been working as a researcher at the Technical University of Munich, Germany, at the Chair of Brewing and Beverage Technology, where she pursues her doctorate in the field ... more

    Prof. Dr. Thomas Brück

    Thomas Brück, born in 1972, obtained his B.Sc. in chemistry, biochemistry and management science from Keele University, Stoke on Trent. Additionally, he holds an M.Sc. in molecular medicine from the same institution. In 2002, Thomas obtained his Ph.D. in Protein Biochemistry from Imperial C ... more

q&more – the networking platform for quality excellence in lab and process

The q&more concept is to increase the visibility of recent research and innovative solutions, and support the exchange of knowledge. In the broad spectrum of subjects covered, the focus is on achieving maximum quality in highly innovative sectors. As a modern knowledge platform, q&more offers market participants one-of-a-kind networking opportunities. Cutting-edge research is presented by authors of international repute. Attractively presented in a high-quality context, and published in German and English, the original articles introduce new concepts and highlight unconventional solution strategies.

> more about q&more

q&more is supported by: