Scientists create DNA flowers that move on their own and deliver medicines

They look like little flowers, bending and unfolding with the changes around them. But they are actually microscopic robots made of DNA and metal that move in response to their environment — and that imitate life.

In a new one, presented in an article published on Monday Nature Nanotechnologya team of researchers from the University of North Carolina (UNC) created “DNA flowers” — tiny hybrid crystals capable of changing shape in seconds.

Researchers intertwined strands of DNA with cobalt phosphateto build each flower, which gives them the ability to fold, shrink and open when the acidity of the medium changes.

Living organisms are constantly remodeling itself: our molecules assemble and disassemble to form adapt to changing conditionsexplains .

Based on this idea, UNC researchers proposed to build materials capable of imitating this ability. Essentially, they wanted to use DNA to create structures that responded to their environment without the need for motors or electronic controls.

Using an enzyme called terminal deoxynucleotidyl transferasethe team spliced ​​together long strands of DNA in the presence of cobalt ions.

As the DNA grew, co-crystallized with cobalt pyrophosphateforming three-dimensional flower-like structures. The process, remarkably, took place in a single Erlenmeyer flask — the type of flask scientists use to mix reagents.

The DNA inside each flower works as a control system incorporated. Under normal conditions, the petals remain open. But when the environment becomes more acidic, parts of DNA fold into special four-stranded shapes called i-motifswhich cause the petals to close.

When the environment returns to normal, the petals open again. This opening and closing can happen many times without damaging the structure.

“It would be extraordinary if we were able to develop smart capsules that automatically activate medication when they detect illness and stop when it is cured”, explains Ronit Freemandirector of the Freeman Lab at UNC and senior author of the study, in a statement published in . “In principle, this could be possible with our shape-shifting materials.”

“No future, flowers that change shapeingestible or implantable, could be designed to deliver a targeted dose of medication, perform a biopsy or unclog a blood clot,” he concludes.

Under the microscope, the nanoflowers are remarkably dynamic. When the surrounding pH changes, the petals shrink to almost half their size in less than a minute, expanding again when conditions normalize.

By changing the sequence and layering of the DNA blocks, the team was able to program different types of movement — shrinkage, curvature, or both.

For example, flowers made from layers alternating inert thymine DNA (T blocks) and reactive cytosine DNA (C blocks) folded their petals like closing buttons. Others done in reverse order they simply contracted inside.

The researchers also built three-block versions that combined both movements simultaneously.

“We took inspiration from nature’s designs, like flowers that bloom or fabric that grows, and translated them into technology that one day could think, move and adapt on its own,” said Freeman.

This precision allows crystals work like machines tiny, capable of transforming chemical changes into movement. Computational models have revealed that scientists can adjust and control its movement just like a mechanical system.

The technology is still in its infancybut its implications are immense.

Researchers envision ingestible or deployable versions that could detect disease markers and release medicines with precision — exactly where needed. For example, cancerous tumors create an acidic environment, so this could lead to targeted therapies.

Another application is cleaning polluted water. Flowers can function as microscopic filters that activate only when toxins are present.

DNA flowers are not alive, but they point to a future where the line between biology and machines becomes increasingly tenuous.