Daniel Ratner, a professor of bioengineering at the University of Washington, has recently developed a way to make regular paper stick to “medically interesting molecules.” That innovation could pave the way for cheap, easy and paper-based tests for diseases like malaria and diabetes.
Currently, paper-based diagnostics like those used for home pregnancy tests rely on nitrocellulose rather than regular paper found in homes and offices.
However, using an inexpensive industrial solvent (divinyl sulfone), Ratner and his research team have been able to transform garden-variety paper into a material that — like nitrocellulose — is “sticky” to diagnostic-enabling chemicals.
“We want to develop something to not just ask a single question but ask many personal health questions,” Ratner said. “‘Is there protein in the urine? Is this person diabetic? Do they have malaria or influenza?’”
To test the concept, Ratner’s team “printed” biomolecules onto the treated paper using an inkjet printer in which the ink was replaced with a sugar called galactose, which attaches to human cells. They were then able to identify the presence of fluorescent ricin, a poison that sticks to galactose, by exposing the treated paper to the poison.
“We wanted to go for the simplest, cheapest starting material, and give it more capability,” Ratner said. “We also wanted to make the system as independent of the end applications as possible, something any researcher could plug into.”