Using silver nanoparticles cloaked in a protein from the HIV virus that has an uncanny ability to penetrate human cells, the scientists have demonstrated that they can enter the inner workings of the nucleus and detect subtle light signals from the "spy."
In order for these nano-spies to be effective, they not only need to get through the cell wall they must be able to enter the nucleus. The ultimate goal is to be able to spot the earliest possible moment when the genetic material within a cell begins to turn abnormal, leading to a host of disorders, especially cancer.
"This new method of getting into and detecting exactly what is going on in the nucleus of cell has distinct advantages over current methods," said Molly Gregas, a graduate student in the laboratory of Tuan Vo-Dinh, R. Eugene and Susie E. Goodson Distinguished Professor of Biomedical Engineering, professor of chemistry and director of The Fitzpatrick Institute for Photonics at Duke's Pratt School of Engineering.
"The ability to place these nanoparticles into a cell's nucleus and gather information using light has potential implications for the selective treatment of disease," Gregas said. "We envision that this approach will also help basic scientists as they try to better understand what occurs within a cell's nucleus."
The researchers coupled miniscule particles of silver, a metal that is not rejected by cells and is an efficient reflector of light, with a small portion of the HIV protein responsible for its highly efficient ability to enter a cell and its nucleus. In this case, the researchers harnessed only the ability of HIV to sneak past cellular defenses, while stripping away its ability to take over the cell's genetic machinery and cause disease.
"This combination takes advantage of the smallness of the nanoparticle and the 'delivery instructions' of the HIV protein," Gregas explained. "Once we can get that nanoparticle into the nucleus, we have many options. We can for example deliver some sort of payload and then observe its effects within the nucleus."
"Our ultimate goal is to develop a nanoscale delivery system that can drop off its payload – in this case nanoparticles with other agents attached – into a cell to enhance the effectiveness of a drug treatment," Vo-Dinh said.
MEDICA.de; Source: Duke University