Scientists develop DNA microcapsules with built-in ion channels

Scientists develop DNA microcapsules with built-in ion channels:

A research group led by Tokyo Tech reports a way of constructing DNA-based microcapsules that hold great promise for the development of new functional materials and devices. They showed that tiny pores on the surface of these capsules can act as ion channels. Their study will accelerate advances in artificial cell engineering and molecular robotics, as well as nanotechnology itself.

DNA-based, self-assembled nanostructures are promising building blocks for new kinds of micro- and nanodevices for biomedical and environmental applications. Much research is currently focused on adding functionality to such structures in order to expand its versatility. For example, engineered capsules called liposomes that have a lipid-bilayer membrane are already successfully being used as sensors, diagnostic tools and drug delivery systems. Another group of capsules that do not have a lipid bilayer but are instead composed of colloidal particle membrane, known as Pickering emulsion or colloidosomes, also have the potential for many biotechnologically useful applications.

Now, a research group led by biophysicist Masahiro Takinoue of Tokyo Institute of Technology reports a new type of Pickering emulsion with the added functionality of ion channels— an achievement that opens new routes to designing artificial cells and molecular robots. For the first time, they have demonstrated ion channel function using pored DNA nanostructures without the presence of a lipid bilayer membrane.

One of the most exciting implications of the study are that it will be possible to develop stimuli-responsive systems—ones that are based on the concept of open-close switching. Such systems could eventually be used to develop artificial neural networks mimicking the way the human brain works. In addition, a stimuli-responsive shape change of the DNA nanoplates could serve as a driving force for autonomous locomotion, which would be useful for the development of molecular robots.

Source: Nano Magazine

Tiny extracts of a precious metal used widely in industry could play a vital role in new cancer therapies

Tiny extracts of a precious metal used widely in industry could play a vital role in new cancer therapies:

Researchers have found a way to dispatch minute fragments of palladium—a key component in motor manufacture, electronics and the oil industry—inside cancerous cells. Scientists have long known that the metal, used in catalytic converters to detoxify exhaust, could be used to aid cancer treatment but, until now, have been unable to deliver it to affected areas.

A molecular shuttle system that targets specific cancer cells has been created by a team at the University of Edinburgh and the Universidad de Zaragoza in Spain. The new method, which exploits palladium's ability to accelerate—or catalyse—chemical reactions, mimics the process some viruses use to cross cell membranes and spread infection. The team has used bubble-like pouches that resemble the biological carriers known as exosomes, which can transport essential proteins and genetic material between cells. These exosomes exit and enter cells, dump their content, and influence how the cells behave.

This targeted transport system, which is also exploited by some viruses to spread infection to other cells and tissues, inspired the team to investigate their use as shuttles of therapeutics.The researchers have now shown that this complex communication network can be hijacked. The team created exosomes derived from lung cancer cells and cells associated with glioma—a tumour that occurs in the brain and spinal cord—and loaded them with palladium catalysts. These artificial exosomes act as Trojan horses, taking the catalysts—which work in tandem with an existing cancer drug- straight to primary tumours and metastatic cells.

Source: Nanomagazine