Tag Archives: Ben-Gurion University of the Negev (BGU)

Nanoscientists speculate that artificial life forms could be medicine of the future

Even after all these years, my jaw is still capable of dropping but then I read the details. This looks a lot like ‘medical nanobots’ which researchers have been talking about for a long time. Nice twist on a familiar theme. From an October 5, 2023 news item on ScienceDaily,

Imagine a life form that doesn’t resemble any of the organisms found on the tree of life. One that has its own unique control system, and that a doctor would want to send into your body. It sounds like a science fiction movie, but according to nanoscientists, it can—and should—happen in the future.

Creating artificial life is a recurring theme in both science and popular literature, where it conjures images of creeping slime creatures with malevolent intentions or super-cute designer pets. At the same time, the question arises: What role should artificial life play in our environment here on Earth, where all life forms are created by nature and have their own place and purpose?

Associate professor Chenguang Lou from the Department of Physics, Chemistry, and Pharmacy, University of Southern Denmark, together with Professor Hanbin Mao from Kent State University, is the parent of a special artificial hybrid molecule that could lead to the creation of artificial life forms. They have now published a review in the journal Cell Reports Physical Science on the state of research in the field behind their creation. The field is called “hybrid peptide-DNA nanostructures,” and it is an emerging field, less than ten years old.

An October 5, 2023 University of Southern Denmark press release (also on EurekAlert) by Birgitte Svennevig, which originated the news item, shares the researcher’s (Chenguang Lou) vision for the research and more technical details about “hybrid peptide-DNA nanostructures” along with other international research efforts,

Lou’s vision is to create viral vaccines (modified and weakened versions of a virus) and artificial life forms that can be used for diagnosing and treating diseases.

“In nature, most organisms have natural enemies, but some do not. For example, some disease-causing viruses have no natural enemy. It would be a logical step to create an artificial life form that could become an enemy to them,” he says.

Similarly, he envisions such artificial life forms can act as vaccines against viral infection and can be used as nanorobots [also known as nanobots] or nanomachines loaded with medication or diagnostic elements and sent into a patient’s body.

“An artificial viral vaccine may be about 10 years away. An artificial cell, on the other hand, is on the horizon because it consists of many elements that need to be controlled before we can start building with them. But with the knowledge we have, there is, in principle, no hindrance to produce artificial cellular organisms in the future,” he says.

What are the building blocks that Lou and his colleagues in this field will use to create viral vaccines and artificial life? DNA and peptides are some of the most important biomolecules in nature, making DNA technology and peptide technology the two most powerful molecular tools in the nanotechnological toolkit today. DNA technology provides precise control over programming, from the atomic level to the macro level, but it can only provide limited chemical functions since it only has four bases: A, C, G, and T. Peptide technology, on the other hand, can provide sufficient chemical functions on a large scale, as there are 20 amino acids to work with. Nature uses both DNA and peptides to build various protein factories found in cells, allowing them to evolve into organisms.

Recently, Hanbin Mao and Chenguang Lou have succeeded in linking designed three-stranded DNA structures with three-stranded peptide structures, thus creating an artificial hybrid molecule that combines the strengths of both. This work was published in Nature Communications in 2022. (read the article here “Chirality transmission in macromolecular domains” and the press release at https://www.sdu.dk/en/om_sdu/fakulteterne/naturvidenskab/nyheder-2022/supermolekyle)

Elsewhere in the world, other researchers are also working on connecting DNA and peptides because this connection forms a strong foundation for the development of more advanced biological entities and life forms.

At Oxford University, researchers have succeeded in building a nanomachine made of DNA and peptides that can drill through a cell membrane, creating an artificial membrane channel through which small molecules can pass. (Spruijt et al., Nat. Nanotechnol. 2018, 13, 739-745)

At Arizona State University, Nicholas Stephanopoulos and colleagues have enabled DNA and peptides to self-assemble into 2D and 3D structures. (Buchberger et al., J. Am. Chem. Soc. 2020, 142, 1406-1416)

At Northwest University [Northwestern University?], researchers have shown that microfibers can form in conjunction with DNA and peptides self-assembling. DNA and peptides operate at the nano level, so when considering the size differences, microfibers are huge. (Freeman et al., Science, 2018, 362, 808-813)

At Ben-Gurion University of the Negev, scientists have used hybrid molecules to create an onion-like spherical structure containing cancer medication, which holds promise to be used in the body to target cancerous tumors. (Chotera et al., Chem. Eur. J., 2018, 24, 10128-10135)

“In my view, the overall value of all these efforts is that they can be used to improve society’s ability to diagnose and treat sick people. Looking forward, I will not be surprised that one day we can arbitrarily create hybrid nanomachines, viral vaccines and even artificial life forms from these building blocks to help the society to combat those difficult-to-cure diseases. It would be a revolution in healthcare,” says Chenguang Lou.

Here’s a link to and a citation for the latest paper,

Peptide-DNA conjugates as building blocks for de novo design of hybrid nanostructures by Mathias Bogetoft Danielsen, Hanbin Mao, Chenguang Lou. Cell Reports Physical Science Volume 4, Issue 10, 18 October 2023, 101620 DOI: https://doi.org/10.1016/j.xcrp.2023.101620

This paper is open access.

Bacteria and an anti-biofilm coating from Ben Gurion University of the Negev (Israel)

This anti-biofilm acts as an anti-adhesive and is another approach to dealing with unwanted bacteria on medical implants and on marine equipment. From an April 25, 2016 news item about the Israeli research on ScienceDaily,

Researchers at Ben-Gurion University of the Negev (BGU) have developed an innovative anti-biofilm coating, which has significant anti-adhesive potential for a variety of medical and industrial applications.

According to the research published in Advanced Materials Interfaces, anti-adhesive patches that are developed from naturally occurring biomaterials can prevent destructive bacterial biofilm from forming on metal surfaces when they are immersed in water and other damp environments.

An April 25, 2016 American Associates Ben Gurion University of the Negev news release (also on EurekAlert), which originated the news item, describes the research further without adding much detail (Note: A link has been removed),

“Our solution addresses a pervasive need to design environmentally friendly materials to impede dangerous surface bacteria growth,” the BGU researchers from the Avram and Stella Goldstein-Goren Department of Biotechnology Engineering explain. “This holds tremendous potential for averting biofilm formed by surface-anchored bacteria and could have a tremendous impact.”

biofouling

Above: SEM micrographs of A. baumannii, P. aeruginosa (PA14), S. marcescens and P.stuartii biofilm architectures. The untreated control surface shows intricate bacteria densely embedded in the matrix. Biofilms were grown statically on the different surfaces.

The anti-adhesive could be used on medical implants, devices and surgical equipment where bacteria can contribute to chronic diseases, resist antibiotic treatment and thereby compromise the body’s defense system. The prevention of aquatic biofouling on ships and bridges is one of the industrial applications.

Here’s a link to and a citation for the paper,

Novel Anti-Adhesive Biomaterial Patches: Preventing Biofilm with Metal Complex Films (MCF) Derived from a Microalgal Polysaccharide by Karina Golberg, Noa Emuna, T. P. Vinod, Dorit van Moppes, Robert S. Marks, Shoshana Malis Arad, and Ariel Kushmaro. Advanced Materials DOI: 10.1002/admi.201500486 Article first published online: 17 MAR 2016

© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This article is behind a paywall.

The world’s smallest diode is made from a single molecule

Both the University of Georgia (US) and the American Associates Ben-Gurion University of the Negev (Israel) have issued press releases about a joint research project resulting in the world’s smallest diode.

I stumbled across the April 4, 2016 University of Georgia news release on EurekAlert first,

Researchers at the University of Georgia and at Ben-Gurion University in Israel have demonstrated for the first time that nanoscale electronic components can be made from single DNA molecules. Their study, published in the journal Nature Chemistry, represents a promising advance in the search for a replacement for the silicon chip.

The finding may eventually lead to smaller, more powerful and more advanced electronic devices, according to the study’s lead author, Bingqian Xu.

“For 50 years, we have been able to place more and more computing power onto smaller and smaller chips, but we are now pushing the physical limits of silicon,” said Xu, an associate professor in the UGA College of Engineering and an adjunct professor in chemistry and physics. “If silicon-based chips become much smaller, their performance will become unstable and unpredictable.”

To find a solution to this challenge, Xu turned to DNA. He says DNA’s predictability, diversity and programmability make it a leading candidate for the design of functional electronic devices using single molecules.

In the Nature Chemistry paper, Xu and collaborators at Ben-Gurion University of the Negev describe using a single molecule of DNA to create the world’s smallest diode. A diode is a component vital to electronic devices that allows current to flow in one direction but prevents its flow in the other direction.

Xu and a team of graduate research assistants at UGA isolated a specifically designed single duplex DNA of 11 base pairs and connected it to an electronic circuit only a few nanometers in size. After the measured current showed no special behavior, the team site-specifically intercalated a small molecule named coralyne into the DNA. They found the current flowing through the DNA was 15 times stronger for negative voltages than for positive voltages, a necessary feature of a diode.

“This finding is quite counterintuitive because the molecular structure is still seemingly symmetrical after coralyne intercalation,” Xu said.

A theoretical model developed by Yanantan Dubi of Ben-Gurion University indicated the diode-like behavior of DNA originates from the bias voltage-induced breaking of spatial symmetry inside the DNA molecule after the coralyne is inserted.

“Our discovery can lead to progress in the design and construction of nanoscale electronic elements that are at least 1,000 times smaller than current components,” Xu said.

The research team plans to continue its work, with the goal of constructing additional molecular devices and enhancing the performance of the molecular diode.

The April 4, 2016 American Associates Ben-Gurion University of the Negev press release on EurekAlert covers much of the same ground while providing some new details,

The world’s smallest diode, the size of a single molecule, has been developed collaboratively by U.S. and Israeli researchers from the University of Georgia and Ben-Gurion University of the Negev (BGU).

“Creating and characterizing the world’s smallest diode is a significant milestone in the development of molecular electronic devices,” explains Dr. Yoni Dubi, a researcher in the BGU Department of Chemistry and Ilse Katz Institute for Nanoscale Science and Technology. “It gives us new insights into the electronic transport mechanism.”

Continuous demand for more computing power is pushing the limitations of present day methods. This need is driving researchers to look for molecules with interesting properties and find ways to establish reliable contacts between molecular components and bulk materials in an electrode, in order to mimic conventional electronic elements at the molecular scale.

An example for such an element is the nanoscale diode (or molecular rectifier), which operates like a valve to facilitate electronic current flow in one direction. A collection of these nanoscale diodes, or molecules, has properties that resemble traditional electronic components such as a wire, transistor or rectifier. The emerging field of single molecule electronics may provide a way to overcome Moore’s Law– the observation that over the history of computing hardware the number of transistors in a dense integrated circuit has doubled approximately every two years – beyond the limits of conventional silicon integrated circuits.

Prof. Bingqian Xu’s group at the College of Engineering at the University of Georgia took a single DNA molecule constructed from 11 base pairs and connected it to an electronic circuit only a few nanometers in size. When they measured the current through the molecule, it did not show any special behavior. However, when layers of a molecule called “coralyne,” were inserted (or intercalated) between layers of DNA, the behavior of the circuit changed drastically. The current jumped to 15 times larger negative vs. positive voltages–a necessary feature for a nano diode. “In summary, we have constructed a molecular rectifier by intercalating specific, small molecules into designed DNA strands,” explains Prof. Xu.

Dr. Dubi and his student, Elinor Zerah-Harush, constructed a theoretical model of the DNA molecule inside the electric circuit to better understand the results of the experiment. “The model allowed us to identify the source of the diode-like feature, which originates from breaking spatial symmetry inside the DNA molecule after coralyne is inserted.”

There’s an April 4, 2016 posting on the Nanoclast blog (on the IEEE [Institute of Electrical and Electronics Engineers] website) which provides a brief overview and a link to a previous essay, Whatever Happened to the Molecular Computer?

Here’s a link and citation for the paper,

Molecular rectifier composed of DNA with high rectification ratio enabled by intercalation by Cunlan Guo, Kun Wang, Elinor Zerah-Harush, Joseph Hamill, Bin Wang, Yonatan Dubi, & Bingqian Xu. Nature Chemistry (2016) doi:10.1038/nchem.2480 Published online 04 April 2016

This paper is behind a paywall.