These protein markers, called PSA for prostate-specific antigen, are found at elevated levels in the blood of men with prostate cancer, which is the number two killer of men in this country.
"The technique is sensitive enough to detect levels 20 times lower than the clinically relevant threshold," said lead author Arun Majumdar, professor of mechanical engineering at the University of California, Berkeley. "This is currently as good as and potentially better than the ELISA assay, which is the standard today for detecting protein markers like PSA."
The microcantilever technique has far broader applications, however. Any disease, ranging from breast cancer to AIDS, characterized by protein or DNA markers in blood or urine could conceivably be assayed by arrays of these microcantilevers. A microcantilever array would be one of the first "protein chips," analogous to the DNA chip used broadly today in research labs and the biotechnology industry to conduct hundreds of DNA analyses simultaneously.
"This offers the possibility of a common platform for high-throughput detection of proteins, DNA and/or RNA, in areas ranging from disease diagnosis to drug discovery," said Majumdar, a member of UC Berkeley's Health Sciences Initiative. "This could lead to fast screening and molecular profiling for many diseases and a possible cancer chip for detecting cancer."
"A big advantage of this technology is that one could look at multiple markers in a single reaction, whereas currently available assays require a separate reaction for each analyte," said colleague Richard J. Cote, MD, profess
Contact: Robert Sanders
University of California - Berkeley