Posted: October 11, 2006

Researchers develop nanomaterial bio-sensor

(Nanowerk News) New Mexico Tech researchers have developed a highly sensitive nucleotide sensor that uses the special light-emitting properties of some nanoparticles in analyzing and identifying individual components of single strands of DNA and RNA.
The nucleotide sensor design, which is described in a technical paper to be published in an upcoming issue of the Journal of the American Chemical Society, is touted as being “versatile and easy to implement” in DNA/RNA research studies and analyses in molecular biology, genetics, and molecular medicine.
With additional refinements to this emerging technology they have designed and developed, the New Mexico Tech scientists also hope to eventually adapt these tiny sensors to detect cancer cells forming in their early stages, as well as to actually target and destroy cancerous cells and tissue.
New Mexico Tech chemistry assistant professor Peng Zhang, Tech biology professor Snezna Rogelj, and Tech students Khoi Nguyen and Damon Wheeler are the university researchers cited as co-authors of the JACS-accepted article, titled “Design of a Highly Sensitive and Specific Nucleotide Sensor Based on Photon Upconverting Particles.
The design and development of the novel sensor is based on using a type of nanomaterial, or materials in the nanometer (10 to the negative 9th power) range, with unique “photon upconversion” properties, meaning that these nanomaterials emit light at shorter wavelengths than the light to which they have been exposed.
“In a proof-of-concept experiment, the designed nucleotide sensor displays high sensitivity and specificity, with the capability of differentiating a single-base mismatch in a 26-base nucleotide target,” said Zhang. “This is an important finding in relation to the study and treatment of many genetic-based diseases, such as Sickle Cell Anemia, which are due to a single-base mismatch on just one base protein.”
The New Mexico Tech researchers applied proven techniques of combining biocompatible nanoparticles with DNA strands to further synthesize photon-upconverting nanoparticles for specific biosensing applications.
“Once such upconverting nanoparticles are prepared, their surfaces can be easily modified to be able to bind to certain proteins or biomolecules of interest,” Zhang explained. “In addition, because most non-target materials used in the study do not possess upconversion properties, an enhanced signal-to-noise ratio is expected when these phosphor nanoparticles are used for sensing, imaging, and luminescent reporting.”
Zhang said he and his fellow research team members are hoping to make the technology they have developed even more “useful and meaningful” by soon adapting it to detect and kill cancer cells.
“I am very excited about the potential for this new application, especially since the preliminary phase of this study has shown that we can identify cancer cells,” Zhang said. “The next step will be to modify these nanoparticle sensors to allow them to be used in photodynamic therapy and actually kill cancer cells with them.”
The continuing research study being conducted by Zhang and his colleagues at New Mexico Tech is funded through start-up financial and logistical support provided by the research university in Socorro.
Source: New Mexico Tech (George Zamora)