Smelling Cancer With Nanotechnology

We have known for years that dogs are capable of smelling cancer on a person's breath or urine. Now scientists are developing nanotech protein sensor arrays for "smelling" cancer--as early screening tests.

To create the protein sensors, the scientists used six gold nanoparticle–fluorescent polymer conjugates. These particles serve as both selective recognition elements as well as quenchers for the polymer. The subsequent binding of protein analytes displaces the dyes, regenerating the fluorescence.

....By modulating the nanoparticle–protein and/or nanoparticle–dye association, distinct signal response patterns can then be used to differentiate the proteins. The fluorescent indicator displacement assay does not require special instruments, and its sensitivity (due in large part to the high surface area provided by the nanoparticles) and speed facilitate protein detection.
Rotello points out that real-world applications require identification of proteins at varying concentrations and of unknown identity. "Varying protein concentrations would be expected to lead to the drastic alteration of fluorescence response patterns for the proteins, making identification of proteins with both unknown identity and concentration challenging. To enable the detection of unknown proteins, we have designed a protocol combining LDA and ultraviolet (UV) measurements."
In their experiments, the researchers also used a series of unknown protein solutions for quantitative detection. The unknown protein solutions were submitted to the testing procedures: of the 52 unknown protein samples, only three samples were incorrectly identified, affording an identification accuracy of 94.2%.
"Our overall goal is to develop a more holistic approach to detecting diseases" says Rotello. "The plan is to monitor levels of proteins in the body, as opposed to looking for just a single marker." Of course, the key question is whether disease can effectively be 'smelled' – are there detectable differences in the relative ratios of proteins that can be used for diagnostic purposes?"

Source

Hat tip Our Technological Future and Nanotechnology Now.

The potential for near-term development of nano-sensors for health care, research, and industrial safety and process control, is enormous. In ten years it will be difficult to imagine life without ubiquitous nano-sensors, just as it is difficult now to imagine life without cell phones, wireless internet, and mp3 players.
;-)

Inexpensive urine tests and breath tests will provide physicians and practitioners with early alerts that should save tens of thousands of lives a year, at the least. As the technology improves, the utility of these nano-sensors will grow as their dimensions shrink.