‘Nanobubbles’ Kill Diseased Cells While Leaving Healthy Cells Untouched
New discovery could replace cell processing in cancer treatment and other disease therapies (Dec. 3)
Researchers at Rice University in Houston, Texas, have found a way to kill some diseased cells and treat others in the same sample at the same time. The process — activated by a pulse of laser light — leaves neighboring healthy cells untouched.
The unique use for “tunable plasmonic nanobubbles” shows promise to replace several difficult processes currently used to treat cancer patients, among others, the researchers say.
The study was published in the American Chemical Society journal ACS Nano.
Plasmonic nanobubbles — which are 10,000 times smaller than a human hair — cause tiny explosions. The bubbles form around plasmonic gold nanoparticles that heat up when excited by an outside energy source — in this case, a short laser pulse — and vaporize a thin layer of liquid near the particle’s surface. The vapor bubble quickly expands and collapses. Biochemist Dr. Dmitri Lapotko and his colleagues had already found that plasmonic nanobubbles kill cancer cells by literally exploding them without damage to healthy neighbors — a process that showed much higher precision and selectivity compared with the use of gold nanoparticles alone, he said.
In the new research, a single laser pulse created large plasmonic nanobubbles around hollow gold nanoshells, and those bubbles selectively destroyed unwanted cells. The same laser pulse created smaller nanobubbles around solid gold nanospheres, which punched tiny, temporary pores in cell walls and created an inbound nanojet that rapidly “injected” drugs or genes into the other cells.
Most disease-fighting and gene therapies require ex vivo processing of human cell grafts to eliminate unwanted cells, such as cancer cells, and to genetically modify other cells to increase their therapeutic efficiency, Lapotko said.
“Current cell processing is often slow, expensive, and labor intensive and suffers from high cell losses and poor selectivity,” he remarked. “Ideally, both elimination and transfection — the introduction of materials into cells — should be highly efficient, selective, fast, and safe.”
Plasmonic nanobubble technology promises “a method of doing multiple things to a cell population at the same time,” said Dr. Malcolm Brenner, who collaborated with the Rice team. “For example, if I want to put something into a stem cell to make it turn into another type of cell, and at the same time kill surrounding cells that have the potential to do harm when they go back into a patient — or into another patient — these very tunable plasmonic nanobubbles have the potential to do that.”
The new research was supported by the National Institutes of Health.
Source: Rice University; December 3, 2012.