Story content courtesy of the University of Georgia, US
In a series of studies, the scientists were able to detect compounds such as lactic acid and the protein albumin in highly diluted samples and in mixtures that included dyes and other chemicals. Their results suggest that the same system could be used to detect pathogens and contaminants in biological mixtures such as food, blood, saliva and urine.
“The results are unambiguous and quickly give you a high degree of specificity,” said senior author Yiping Zhao, professor of physics in the UGA Franklin College of Arts and Sciences and director of the university’s Nanoscale Science and Engineering Center.
To test their method, the researchers used mixtures of dyes, the organic chemical melamine, lactic acid and the protein albumin. In each case, they were able to directly identify the compounds of interest, even in samples diluted to concentrations below 182 nanograms per milliliter—roughly 200 billionths of a gram in a fifth of a teaspoon. And while the detection of viruses using techniques such as polymerase chain reaction can take days or even weeks and requires fluorescent labels, the on-chip method developed by the UGA researchers yields results in less than an hour without the use of molecular labels.
The research was supported by the U.S. Department of Agriculture, the National Science Foundation and the UGA College of Agricultural and Environmental Sciences.