Development of a Sensitive Microcantilever Instrument for Detecting the Protein Markers on Prostate Cancer


Researchers at ORNL and UC Berkeley reported in Nature Biotechnology that they have developed a very sensitive microcantilever instrument for detecting the protein markers for prostate cancer. The instrument works by inducing the cancer markers to stick to and ultimately bend a microscopic cantilever (a microscopic diving board that is smaller than a human hair). The protein markers, called PSA for prostate-specific antigen, are found at elevated levels in the blood of men with prostate cancer. When the cancer protein molecules bind to the surface of the microcantilever, which are 50 microns wide (half the width of a human hair), the cantilever bends about 10-20 nanometer – the diameter of 100-200 hydrogen atoms. A sensitive laser detects and measures the minute movement of the cantilever thus signaling the presences of increased levels of PSA. The researchers report that the instrument is sensitive enough to detect PSA levels 20 times lower than the clinically relevant threshold. Research is supported by the BER Advanced Medical Technology Program.