Novel DNA-peptide structure holds promise for multicoloured roll-up displays

The research from Tel Aviv University is said to harness bionanotechnology to emit a full range of colours in one pliable pixel layer compared to the several rigid layers that constitute today’s screens.

“Our material is light, organic, and environmentally friendly,” said Prof Ehud Gazit, from the Department of Molecular Microbiology and Biotechnology at TAU’s Faculty of Life Sciences. “It is flexible, and a single layer emits the same range of light that requires several layers today. By using only one layer, you can minimise production costs dramatically, which will lead to lower prices for consumers as well.”

Prof Gazit conducted the research with doctoral student Or Berger in collaboration with Dr Yuval Ebenstein and Prof Fernando Patolsky of the School of Chemistry at TAU’s Faculty of Exact Sciences.

For the purpose of the study, a part of Berger’s Ph.D. thesis, the researchers tested different combinations of peptides: short protein fragments, embedded with DNA elements which facilitate the self-assembly of a unique molecular architecture.

Peptides and DNA are two of the most basic building blocks of life. Each cell of every life form is composed of such building blocks and in the field of bionanotechnology, scientists utilise these building blocks to develop novel technologies with properties not available for inorganic materials such as plastic and metal.

“Our lab has been working on peptide nanotechnology for over a decade, but DNA nanotechnology is a distinct and fascinating field as well…I wanted to try and converge the two approaches,” Berger said in a statement. “In this study, we focused on PNA - peptide nucleic acid, a synthetic hybrid molecule of peptides and DNA. We designed and synthesised different PNA sequences, and tried to build nano-metric architectures with them.”

Using electron microscopy and X-ray crystallography, the researchers discovered that three of the molecules they synthesised could quickly self-assemble into ordered structures. The structures are said to have resembled the natural double-helix form of DNA, but also exhibited peptide characteristics. This resulted in a unique molecular arrangement that reflects the duality of the new material.

“Once we discovered the DNA-like organisation, we tested the ability of the structures to bind to DNA-specific fluorescent dyes,” said Berger. “To our surprise, the control sample, with no added dye, emitted the same fluorescence as the variable. This proved that the organic structure is itself naturally fluorescent.”

The structures were found to emit light in every colour, compared to other fluorescent materials that shine only in one specific colour. Moreover, light emission was observed also in response to electric voltage, which make it suitable for optoelectronic devices like display screens.

The research was recently published in Nature Nanotechnology.