Glowing DNA Origami Helps Caltech Scientists Recreate Van Gogh's Starry Night


Whoever says the Arts and Sciences can't ever intermingle obviously has to see this new masterpiece.

A team of scientists at the California Institute of Technology (Caltech) has recreated a famous painting by post-Impressionist artist Vincent Van Gogh known as "The Starry Night."

But here's the twist: Caltech scientists did not make use of any conventional painting methods.

Instead, with the help of an incredible technique called DNA origami, they used folded DNA to place fluorescent molecules within tiny light resonators.

The end result is a spectacular monochrome image the width of a dime across that appears like Van Gogh's work of art.

What Is DNA Origami?

Paul Rothemund, a Caltech alumnus, developed the process of DNA origami exactly 10 years ago. The technique allows experts to fold a long strand of DNA and turn them into any shape.

The folded and manipulated DNA acts a scaffold onto which scientists can stick and organize any kind of components on the nanometer scale, including glowing molecules, electrically conductive carbon nanotubes and even drugs.

Rothemund, now a research professor, compares DNA origami and the folded DNA to pegboards people use to organize tools in the garage.

But in this case, the "pegboard" assembles itself from folded DNA strands and the tools can find their own positions.

The process all happens in a test tube, without even needing human intervention, says Rothemund.

This is crucial because all of the parts are too microscopic to be manipulated efficiently, and because Rothemund and his team wanted to produce billions of the strands.

"Spray And Pray"

For some applications, the organization of nanoscale components to produce devices on the DNA pegboards is not sufficient. The devices need to be formed together to create a larger circuit and require a method to communicate with larger scale devices.

An initial approach was to develop electrodes first and then spread devices randomly on a surface, with the expectation that at least a few of the strands would land in desired locations -- a method Rothenmund calls "spray and pray."

How Caltech's "The Starry Night" Was Made

Seven years ago, Rothenmund and his colleagues at IBM Research described a process through which DNA origami could be placed at exact locations on surfaces.

The technique required electron-beam lithography to engrave sticky binding sites that have the exact shape as the origami.

Since then, Rothenmund and Ashwin Gopinath have refined this technique so that DNA shapes can be accurately positioned on nearly any surface used in the development of computer chips.

The first application of their enhanced technique used DNA origami to put fluorescent molecules into minute light sources.

Rothemund says it's like using the process to screw microscopic light bulbs into molecular lamps.

In the research, the lamps are phototonic crystal cavities (PCCs) -- microfabricated structures that are tuned to resonate at a specific wavelength of light. It's similar to how a tuning fork vibrates with a certain pitch.

A PCC, which is developed within a thin glass-like membrane, takes the form of a defect within a honeycomb of holes.

Researchers moved the PCCs in 20 nanometer steps and mapped out a checkerboard pattern of spots, where the molecular lights are either glowing intensely or strongly. They were able to place glowing molecules to make lamps of different intensities. Hence, the work of art was formed.

Practical Applications

Caltech researchers believe that the process involved in DNA origami can potentially influence a wide range of fields, from the construction of nanoscale computers to drug delivery.

Meanwhile, scientists are now working to improve the light emitters. As of writing, the fluorescent molecules could only work for approximately 45 seconds before they react with oxygen and dying. The molecules could also only generate a few shades of red rather than a single pure color.

Should experts solve these issues, the field of quantum computing will be forever changed.

"[T]here's a lot of fundamental science to be done," adds Gopinath.

Details of the study are published in the journal Nature.

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