Scientists have found a way to ‘tattoo’ living cells with gold: ScienceAlert

It may seem like the perfect solution, but the new technique of tattooing gold on living tissue is a step toward integrating human cells with electronic devices.

By relying on a manufacturing technique called nanolithography, the scientists printed a live mouse embryo Fibroblasts With patterns of gold dots and nanowires. They say this is an important first step toward adding more complex circuits.

And it’s not just because cyborgs are cool. And according to the scientists who developed it, led by engineer David Gracias of Johns Hopkins University, this technology could have amazing health applications.

“If you imagine where all this will go in the future, we would like to have sensors to remotely monitor and control the status of individual cells and the environment around those cells in real time.” says Gracias.

“If we had techniques to track the health of isolated cells, perhaps we could diagnose and treat diseases much earlier and not wait for the whole organ to be damaged.”

Engineers have been searching for a way to integrate electronics with human biology for some time, but there are significant roadblocks along the way. One of the biggest hurdles is the incompatibility of living tissue with the manufacturing techniques used in electronics.

Although there are ways to make things small and flexible, they often use harsh chemicals, high temperatures, or vacuum cleaners that destroy living tissue or soft, water-based materials.

Gracias and his team built on their technique Nanolithography Which is very much what it sounds like: using a stamp to print nanoscale patterns onto the material. Here, the material is gold, but that’s just the first step of the process. Once the model is made, it must be transferred and attached to living tissue.

The researchers first printed the nanoscale gold onto a coated silicon wafer polymer. Next, the polymer was melted so that the pattern could be transferred to thin films of glass, where it was treated with a biological compound called cystamineand hydrogel-coated.

Then the model was removed from the glass and processed gelatinbefore being transferred to a fibroblast. Finally, the hydrogel was dissolved. Cystamine and gelatin helped bind the gold to the cell, where it remained and moved with the cell for the next 16 hours.

They used the same technique to attach arrays of gold nanowires to it ex vivo rat brains. But they say fibroblasts represent the most exciting finding.

“We have shown that we can attach complex nanopatterns to living cells, while ensuring that the cell does not die.” says Gracias.

“It’s a very important finding that cells can live and move around with tattoos because there is often a huge incompatibility between living cells and the methods that engineers use to manufacture electronics.”

Because nanolithography is relatively simple and low-cost, this work represents a way forward in the development of more complex electronics such as electrodes, antennas, and circuits, to be integrated not only with living tissues, but also hydrogels And other soft materials that are not compatible with harsh manufacturing methods.

“We anticipate this nanopatterning process, along with different classes of materials and standard microfabrication techniques such as photolithography and electron beam lithography.” write the researchers“To open opportunities for the development of novel cell culture substrates, hybrid biomaterials, electronic devices and biosensors.”

The research has been published in Nano Letters.