Scientists Capture Image of DNA for the First Time
For the first time, scientists have captured the image (see photo) of a double helix DNA, a structure that is essential to all forms of life.
DNA molecules encode genetic instructions that play a significant role in the development of living organisms. The shape of DNA was first devised by scientists James Watson and Francis Crick in 1953.
Until now, researchers knew that DNA is a helix-shaped structure discovered using a technique called X-ray crystallography. This method is used to convert patterns of dots into an image, Discovery News reported.
Now, Enzo Di Fabrizio, a physics professor at the Magna Graecia University in Catanzaro, Italy, has pictured the image of DNA molecules using a scanning electron microscope.
A report in New Scientist says Fabrizio and his colleagues developed a technique that pulls DNA threads out of a dilute solution, and placed them on nanoscopic water-repellant silicon pillars.
When the DNA strands, snagged out of the liquid solution, were added into the silicon pillars, it evaporated the water, leaving the strands to stretch out and made available to view.
The researchers then drilled holes in the silicon bed and beamed electrons through the holes. This way, they were able to take high resolution images of the DNA molecules. The images reveal the double-corkscrew thread of the DNA.
The New Scientist report notes that the technique works with DNA chords that have around seven strands wrapped in it. This is because the energy from the electrons is high enough to break a single strand of DNA.
Using more sensitive detectors and low-energy electrons, the research team is hoping to capture the images of individual double helices.
The findings of the study are published in the journal NanoLetters.