March 4, 2004

Ultra-sensitive technology may aid cancer detection

By Megan Fellman

Scientists at Northwestern have developed an ultra-sensitive technology based on gold nanoparticles and DNA that can detect prostate specific antigen when present at extremely low levels in a blood sample. This promising new protein-detection method could be used to monitor prostate cancer patients following surgery and to detect the early signs of breast cancer.

Prostate cancer in men and breast cancer in women are the second leading causes of cancer deaths in the United States. (Only lung cancer is more deadly.) The life-saving potential of early detection has been well established for years, and improved cancer screening methods have helped to reduce the threat.

The researchers have demonstrated that their method is a million times more sensitive than conventional methods, a feature that promises to change dramatically the way proteomics (the study and analysis of protein structure and function) and medical diagnostics are done. The results were published in the journal Science.

“The polymerase chain reaction, which duplicates DNA so it can be analyzed, revolutionized forensics, medicine and biotechnology,” said Chad A. Mirkin, director of Northwestern’s Institute for Nanotechnology, who led the research team, “but we haven’t had anything of comparable sensitivity for proteins. Now we do. This technology will change the way we do cancer diagnostics and treatment.”