How To Fix Duchenne Muscular Dystrophy

Scientists at the University of California, Berkeley, have engineered a new way to deliver CRISPR-Cas9 gene-editing technology inside cells and have demonstrated in mice that the technology can repair the mutation that causes Duchenne muscular dystrophy, a severe muscle-wasting disease. A new study shows that a single injection of CRISPR-Gold, as the new delivery system is called, into mice with Duchenne muscular dystrophy led to an 18-times-higher correction rate and a two-fold increase in a strength and agility test compared to control groups.

Since 2012, when study co-author Jennifer Doudna, a professor of molecular and cell biology and of chemistry at UC Berkeley, and colleague Emmanuelle Charpentier, of the Max Planck Institute for Infection Biology, repurposed the Cas9 protein to create a cheap, precise and easy-to-use gene editor, researchers have hoped that therapies based on CRISPR-Cas9 would one day revolutionize the treatment of genetic diseases. Yet developing treatments for genetic diseases remains a big challenge in medicine. This is because most genetic diseases can be cured only if the disease-causing gene mutation is corrected back to the normal sequence, and this is impossible to do with conventional therapeutics.

CRISPR/Cas9, however, can correct gene mutations by cutting the mutated DNA and triggering homology-directed DNA repair. However, strategies for safely delivering the necessary components (Cas9, guide RNA that directs Cas9 to a specific gene, and donor DNA) into cells need to be developed before the potential of CRISPR-Cas9-based therapeutics can be realized. A common technique to deliver CRISPR-Cas9 into cells employs viruses, but that technique has a number of complications. CRISPR-Gold does not need viruses.

In the new study, research lead by the laboratories of Berkeley bioengineering professors Niren Murthy and Irina Conboy demonstrated that their novel approach, called CRISPR-Gold because gold nanoparticles are a key component, can deliver Cas9 – the protein that binds and cuts DNA – along with guide RNA and donor DNA into the cells of a living organism to fix a gene mutation.

CRISPR-Gold is the first example of a delivery vehicle that can deliver all of the CRISPR components needed to correct gene mutations, without the use of viruses,” Murthy said.

The study was published in the journal Nature Biomedical Engineering.


How To Harvest Heat In The Dark To Produce Electricity

Physicists have discovered radical new properties in a nanomaterial, opening new possibilities for highly efficient thermophotovoltaic cells that could one day harvest heat in the dark and turn it into electricity. The research team from the Australian National University (ANU/ARC Centre of Excellence CUDOS) and the University of California Berkeley demonstrated a new artificial material, or metamaterial, that glows in an unusual way when heated.

The findings could drive a revolution in the development of cells which convert radiated heat into electricity, known as thermophotovoltaic cells. “Thermophotovoltaic cells have the potential to be much more efficient than solar cells,” said Dr Sergey Kruk from the ANU Research School of Physics and Engineering.


Our metamaterial overcomes several obstacles and could help to unlock the potential of thermophotovoltaic cells.”

Thermophotovoltaic cells have been predicted to be more than twice as efficient as conventional solar cells. They do not need direct sunlight to generate electricity, and instead can harvest heat from their surroundings in the form of infrared radiation. They can also be combined with a burner to produce on-demand power or can recycle heat radiated by hot engines. The team’s metamaterial, made of tiny nanoscopic structures of gold and magnesium fluoride, radiates heat in specific directions. The geometry of the metamaterial can also be tweaked to give off radiation in specific spectral range, in contrast to standard materials that emit their heat in all directions as a broad range of infrared wavelengths. This makes the new material ideal for use as an emitter paired with a thermophotovoltaic cell.

The project started when Dr Kruk predicted the new metamaterial would have these surprising properties. The ANU team then worked with scientists at the University of California Berkeley, who have unique expertise in manufacturing such materials.

To fabricate this material the Berkeley team were operating at the cutting edge of technological possibilities,” Dr Kruk said. “The size of an individual building block of the metamaterial is so small that we could fit more than 12,000 of them on the cross-section of a human hair.

The research is published in Nature Communications.


How To Make Objects Invisible

Scientists at the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley have devised an ultra-thin invisibilityskincloak that can conform to the shape of an object and conceal it from detection with visible light. Although this cloak is only microscopic in size, the principles behind the technology should enable it to be scaled-up to conceal macroscopic items as well.

Working with brick-like blocks of gold nanoantennas, the Berkeley researchers fashioned a “skin cloak” barely 80 nanometers in thickness, that was wrapped around a three-dimensional object about the size of a few biological cells and arbitrarily shaped with multiple bumps and dents. The surface of the skin cloak was meta-engineered to reroute reflected light waves so that the object was rendered invisible to optical detection when the cloak is activated.

Invisible objectsA 3D illustration of a metasurface skin cloak made from an ultrathin layer of nanoantennas (gold blocks) covering an arbitrarily shaped object. Light reflects off the cloak (red arrows) as if it were reflecting off a flat mirror

This is the first time a 3D object of arbitrary shape has been cloaked from visible light,” said Xiang Zhang, director of Berkeley Lab’s Materials Sciences Division and a world authority on metamaterials – artificial nanostructures engineered with electromagnetic properties not found in nature. “Our ultra-thin cloak now looks like a coat. It is easy to design and implement, and is potentially scalable for hiding macroscopic objects.”


Smart Bandage

Engineers at UC Berkeley are developing a new type of bandage that does far more than stanch the bleeding from a paper cut or scraped knee.

Associate professor Michel Maharbiz explains how the smart bandage works to detect bedsores. (UC Berkeley video by Roxanne Makasdjian and Phil Ebiner)
Thanks to advances in flexible electronics, the researchers, in collaboration with colleagues at UC San Francisco, have created a new “smart bandage” that uses electrical currents to detect early tissue damage from pressure ulcers, or bedsores, before they can be seen by human eyes – and while recovery is still possible.
The researchers exploited the electrical changes that occur when a healthy cell starts dying. They tested the thin, non-invasive bandage on the skin of rats and found that the device was able to detect varying degrees of tissue damage consistently across multiple animals.

smartbandage The smart bandage is fabricated by printing gold electrodes onto a thin piece of plastic. This flexible sensor uses impedance spectroscopy to detect bedsores that are invisible to the naked eye
We set out to create a type of bandage that could detect bedsores as they are forming, before the damage reaches the surface of the skin,” said Michel Maharbiz, a UC Berkeley associate professor of electrical engineering and computer sciences and head of the smart-bandage project. “We can imagine this being carried by a nurse for spot-checking target areas on a patient, or it could be incorporated into a wound dressing to regularly monitor how it’s healing.
The findings, published in the journal Nature Communications, could provide a major boost to efforts to stem a health problem that affects an estimated 2.5 million U.S. residents at an annual cost of $11 billion.


How To Read DNA At High-Speed

Berkeley Researchers Create Unique Graphene Nanopores with Optical Antennas for DNA Sequencing.
High-speed reading of the genetic code should get a boost with the creation of the world’s first graphene nanoporespores measuring approximately 2 nanometers in diameter – that feature a “built-inoptical antenna. Researchers with Berkeley Lab and the University of California (UC) Berkeley have invented a simple, one-step process for producing these nanopores in a graphene membrane using the photothermal properties of gold nanorods.
graphene nanopore
Schematic drawing of graphene nanopore with self-integrated optical antenna (gold) that enhances the optical readout signal (red) of DNA as it passes through a graphene nanopore

With our integrated graphene nanopore with plasmonic optical antenna, we can obtain direct optical DNA sequence detection,” says Luke Lee, the Arnold and Barbara Silverman Distinguished Professor at UC Berkeley. “We believe our approach opens new avenues for simultaneous electrical and optical nanopore DNA sequencing and for regulating DNA translocation,” says Zettl, who is also a member of the Kavli Energy Nanoscience Institute (Kavli ENSI).


Solar Cells at the Price of Pocketbooks

Engineers at the University of California, Berkeley, have developed an inexpensive new way to grow thin films of a material prized in the semiconductor and photovoltaic industries, an achievement that could bring high-end solar cells within reach of consumer pocketbooks.

solar-satelliteUC Berkeley engineers could help make high-end solar cells, currently used in satellites and other space and military applications, affordable for consumer markets.
Performance is everything in the solar cell industry, but performance at a reasonable cost is key,” said Javey, who is also a faculty scientist at the Lawrence Berkeley National Laboratory. “The techniques we are reporting here should be a game-changer for III-V solar cells, as well as for LEDs.”

Top of the line photovoltaics are made from a class of material known as III-V (pronounced “three-five”) compounds, known for their superior efficiency at converting light into power. However, the complex manufacturing requirements for III-V materials make them up to 10 times more expensive than silicon, limiting their use to military applications and NASA satellites, the researchers said.

The work, led by Ali Javey, UC Berkeley associate professor of electrical engineering and computer sciences, is described in a paper published in Scientific Reports, Nature’s open access journal.

Photovoltaics Everywhere

Solar cells convert sunlight into electricity using semiconductor materials that exhibit the photovoltaic effect – meaning they absorb photons and release electrons that can be channeled into an electrical current. Photovoltaics are the ultimate source of clean, green and renewable energy but today’s  technologies utilize relatively scarce and expensive semiconductors. But now  High efficiency solar cells could be made from virtually any semiconductor material. This technology has been developed by researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UCBerkeley. 

It’s time we put bad materials to good use,” says physicist Alex Zettl, Director of the Center of Integrated Nanomechanical Systems (COINS), who led this research along with colleague Feng Wang. “Our technology allows us to sidestep the difficulty in chemically tailoring many earth abundant, non-toxic semiconductors and instead tailor these materials simply by applying an electric field.”Our technology reduces the cost and complexity of fabricating solar cells and thereby provides what could be an important cost-effective and environmentally friendly alternative that would accelerate the usage of solar energy.”