Tiny Bubbles Destroy Cancer Cells

Tiny bubbles can pack quite a punch — creating nanoscale explosions that destroy cancer cells.

Using lasers and nanoparticles, scientists discovered a new technique for singling out individual diseased cells and demolishing them.

The scientists used lasers to make "nanobubbles" by zapping gold nanoparticles inside cells. In tests on cancer cells, they found they could tune the lasers to create either small, bright bubbles that were visible but harmless or large bubbles that burst the cells.

The term "nano" generally refers to stuff at the nanoscale that's no larger than 100 nanometers, where 1 nanometer is one-billionth of a meter. For comparison, a hair is about 100,000 nm wide.

"Single-cell targeting is one of the most touted advantages of nanomedicine, and our approach delivers on that promise with a localized effect inside an individual cell," said study author Dmitri Lapotko, a physicist at Rice University in Texas. "The idea is to spot and treat unhealthy cells early, before a disease progresses to the point of making people extremely ill."

Previously, the scientists had applied nanobubbles to arterial plaque, and found the bubbles could blast right through the deposits that block arteries.

"The bubbles work like a jackhammer," Lapotko said.{{ video="LS_100205_nanobubbles" title="Nanobubbles Blast Blocked Arteries" caption="Scientists used lasers to make nanobubbles by zapping gold nanoparticles inside cells. In tests they found the nanobubbles could blast through deposits that block arteries. The method also worked to kill cancer cells. Credit: D. Lapotko/Rice University" }}

In the current study, they tested the approach on leukemia cells and cells from head and neck cancers. They attached antibodies to the nanoparticles so they would target only the cancer cells, and they found the technique was effective at locating and killing the cancer cells.

The short-lived bubbles are very bright and can be made smaller or larger by varying the power of the laser. Because they are visible under a microscope, nanobubbles can be used to either diagnose sick cells or to track the explosions that are destroying them.

The results were published online Jan. 25 in the journal Nanotechnology.