This fluorescent micrograph features
a single microgripper with live
cells within its grasp; © John
The mass-producible microgrippers each measure approximately one-tenth of a millimeter in diameter. In lab tests, they have been used to perform a biopsy-like procedure on animal tissue placed at the end of a narrow tube.
David H. Gracias of John Hopkins University, who supervised the research project, explained: "We've demonstrated tiny inexpensive tools that can be triggered en masse by nontoxic biochemicals. This is an important first step toward creating a new set of biochemically responsive and perhaps even autonomous micro- and nanoscale surgical tools that could help doctors diagnose illnesses and administer treatment in a more efficient, less invasive way." However, the devices will require further refinement before they can be used in humans.
Today, doctors who wish to collect cells or manipulate a bit of tissue inside a patient's body often use tethered microgrippers connected to thin wires or tubes. But these tethers can make it difficult navigate the tool through tortuous or hard-to-reach locations. To eliminate this problem, the untethered grippers devised by Gracias' team contain gold-plated nickel, allowing them to be steered by magnets outside the body. "With this method, we were able to remotely move the microgrippers a relatively long distance over tissue without getting stuck”, he said. “Additionally, the microgrippers are triggered to close and extricate cells from tissue when exposed to certain biochemicals or biologically relevant temperatures."
Gracias, who also is affiliated with the Institute for NanoBioTechnology at Johns Hopkins, hopes to collaborate with medical researchers who can help to move the microgrippers closer to use as practical biopsy and drug delivery tools in humans.
COMPAMED.de; Source: Johns Hopkins University