Quantum Dot

Quantum dots have received a good deal of attention in the nano world. It will be interesting to see how Invitrogen's purchase of Quantum Dot evolves in the months ahead...

Analysts are studying last week's acquisition by Invitrogen of Quantum Dot Corp., the nanotech startup that laid claim to all key life-science applications for quantum dots, trying to guess the sale amount and what it might mean for the industry.

Some nanotechnologists consider the sale of the Hayward, Calif., company a success, seeing it as a corporate leader's validation of the company as worthy of investment. Others are not so sure.

"It's nothing of the sort," Matthew Nordan, vice president of research at Lux Research, the nanotechnology analysis firm in New York City, told UPI's Nano World. "Quantum Dot Corporation had a large amount of venture-capital backing behind it, and the acquisition likely did not come close to matching it."

Venture capitalists had invested roughly $45.5 million in Quantum Dot, and although Invitrogen, the biotech giant in Carlsbad, Calif. -- a nearly $3.75 billion market-cap company -- did not reveal how much it spent to acquire the company, given that it acquired Molecular Probes of Eugene, Ore., in 2003 for six times its market valuation, "I would guess that Quantum Dot ... was acquired for $20 to $25 million at best," Nordan said.

Quantum dots are semiconductor crystals only nanometers or billionths of a meter wide. They fluoresce brightly when they absorb even minuscule amounts of light. Scientists can engineer the specific colors of light that quantum dots absorb or emit with extraordinary precision by adjusting their size and makeup. For instance, a cadmium-selenide quantum dot more than 6 nanometers in diameter emits red light, while one less than 3 nanometers wide glows green.

Quantum dots "represent the next generation of imaging," said Invitrogen spokesman Eric Endicott. They could help scientists image the behavior of cells and organs to a level of detail never before seen in the $500 million worldwide market for biological-detection agents.

Conventional fluorescent dyes used in the life sciences to help researchers monitor how cells and organs grow and develop normally lose their ability to emit light within seconds. Quantum dots, on the other hand, last far longer, helping investigators to monitor cells and organs in diseased and healthy conditions on a molecular scale in real time.