Detecting Disease Via Polymerization

Inexpensive, rapid, and robust strategies for detecting diseases are desperately needed in many parts of the world. Numerous diagnostic tests already available require desktop equipment and trained operators, and portable enzyme technologies—such as those found in home pregnancy tests—often are not sensitive enough for detecting diseases. Hadley D. Sikes and Christopher N. Bowman at the University of Colorado, Boulder, and colleagues have used a well-known polymerization reaction, rather than expensive instrumentation, to indicate the presence of zeptomole quantities (10^-21 mole) of biological molecules, a process that eventually could enable direct blood testing from a finger prick (Nat. Mater., DOI: 10.1038/nmat2042). The researchers designed a dual-function molecule that can recognize a target biomolecule and initiate a photopolymerization reaction. The dual-function molecule contains the glycoprotein avidin, which reacts with a biotinylated oligonucleotide, as well as initiators that trigger polymerization of hydroxyethyl acrylate. The resulting polymer spots become visible to the naked eye within a few minutes, indicating the test result.