Physicists maneuver DNA molecules using electrical fields, offering real-time control

Researchers from the McGill Physics Department have developed a new device that can trap and study DNA molecules without touching or damaging them. The device, which uses carefully adjusted electric fields, offers scientists an unprecedented control over the way DNA behaves in real time, creating the opportunity for a faster and more precise molecular analysis which could improve diagnostics, genome mapping and the study of molecules related to the disease.

Doctoral student Matheus Azevedo Silva Pessôa, Nanofluides researcher, developed the tool in collaboration with his workmates in the Nanobiophysical laboratory of Professor Walter Reisner. Researchers from the bio-engineering laboratory of Professor Sara Mahshid in McGill, the startup Genomics Technology Dimension Genomics and the University of California, Santa Barbara have also contributed.

The article, “capture, release and dynamic manipulation of a single molecule via reversible electrocinetic containment (Recon)” Scientific advances.

DNA electrical load operation

“The previous models force you to mechanically control the molecules to trap them,” said Pessôa. “You must limit the molecules in a groove so that you can study them, then mechanically induce a plate or a lid, to push the molecules inside a well. But sometimes they break, and control over the position of these molecules is extremely limited.”

Now, researchers can adjust each DNA molecule more quickly and gently by exploiting its inherent electrical qualities to guide it in a small well.

Like adjusting an AM radio dial

While previous research has attempted to control molecules with electric fields, high tension has often caused various problems that have made this approach impractical.

Pessôa said the new device allows researchers to adjust the electrical voltage to a specific frequency, such as adjusting an AM radio dial. This fine control allows them to trap DNA molecules without damaging them.

Scientists can also release molecules at will. By controlling how close DNA is, they can observe its behavior in real time.

“In this way, we can see the specific DNA dynamics, because we can limit the molecules as long as we want without breaking them, and see what is happening when the electric field that we use to trap them is changed,” he added.

Researchers say that manipulation of DNA to such a small scale can also help to accelerate chemical reactions such as the triggering of liposomes – carriers based on the bulk of pregnancy material – to open and release their content, allowing scientists to study these dynamics further.

The platform could also be used to simulate cellular environments, making it a powerful tool for diagnosis and discovery.

The researcher is one of those listed as inventors of the provisional patent request for a genomics dimension for this device.