Little Boxes On The Hillside? No, In Your Body

“Little boxes, on the hillside, little boxes made of ticky-tacky…”
– Malvina Reynolds, 1962

When folk legend Pete Seeger sang those words 44 years ago, I’ll bet he never imagined this…

The science of nanotechnology – construction of machines at the molecular level – has taken another step forward with the recent development of microscopic metal boxes that hold a few nanoliters of liquid. These containers may eventually be used for precision chemistry and medical applications.

These tiny boxes assemble themselves, and can be moved around using magnetic fields. Such a tool is able to carry small chemical samples around and deliver drugs within the human body, according to researchers.

“We have shown that we can bring two or more of them together to allow the chemicals they hold to react,” says David Gracias, a researcher and chemical engineer at Johns Hopkins University.

These “little boxes” are constructed by depositing layers of nickel chemically on top of a polymer-coated silicon wafer.  An electric current is then applied to bind them together. After this, the metal template is released from the silicon layer by heating the boxes to 250 ºC (about 482ºF), dissolving the polymer.  “The ‘solder’ melts and the very high surface tension causes the liquid to contract and fold the templates spontaneously into 3D boxes,” Gracias says.

The nickel boxes are magnetic, enabling them to be moved and manipulated with magnetic fields. “We’ve shown previously that these boxes can be imaged inside living cells using an MRI scanner,” Gracias says. “Now we’ve demonstrated we can guide them in any trajectory using a magnetic stylus.”

Gracias thinks these  boxes could provide a useful alternative to microfluidic chips currently in use, which use microscopic tubes to direct chemicals around. “These boxes are reconfigurable,” he says. “Once you’ve made your [microfluidic] chip you’re stuck with it.”

Eventually, these little boxes could be used for precision targeting of drugs inside the human body.  Gracias says “We have done preliminary studies in mice and found no toxic effects so far.”

Via New Scientist

“Little boxes, on the hillside, little boxes made of ticky-tacky…”
– Malvina Reynolds, 1962

When folk legend Pete Seeger sang those words 44 years ago, I’ll bet he never imagined this…

The science of nanotechnology – construction of machines at the molecular level – has taken another step forward with the recent development of microscopic metal boxes that hold a few nanoliters of liquid. These containers may eventually be used for precision chemistry and medical applications.

These tiny boxes assemble themselves, and can be moved around using magnetic fields. Such a tool is able to carry small chemical samples around and deliver drugs within the human body, according to researchers.

“We have shown that we can bring two or more of them together to allow the chemicals they hold to react,” says David Gracias, a researcher and chemical engineer at Johns Hopkins University.

These “little boxes” are constructed by depositing layers of nickel chemically on top of a polymer-coated silicon wafer.  An electric current is then applied to bind them together. After this, the metal template is released from the silicon layer by heating the boxes to 250 ºC (about 482ºF), dissolving the polymer.  “The ‘solder’ melts and the very high surface tension causes the liquid to contract and fold the templates spontaneously into 3D boxes,” Gracias says.

The nickel boxes are magnetic, enabling them to be moved and manipulated with magnetic fields. “We’ve shown previously that these boxes can be imaged inside living cells using an MRI scanner,” Gracias says. “Now we’ve demonstrated we can guide them in any trajectory using a magnetic stylus.”

Gracias thinks these  boxes could provide a useful alternative to microfluidic chips currently in use, which use microscopic tubes to direct chemicals around. “These boxes are reconfigurable,” he says. “Once you’ve made your [microfluidic] chip you’re stuck with it.”

Eventually, these little boxes could be used for precision targeting of drugs inside the human body.  Gracias says “We have done preliminary studies in mice and found no toxic effects so far.”

Via New Scientist