The nano-scale PAMAM dendrimers were chosen because their size and surface dimension could accommodate multiple anti-epithelial cell adhesion molecules, Hong said. This enabled the multivalent binding, along with the physiological process of "cell rolling" induced by E-selectin, which mimics the process by which circulating tumor cells are recruited to the endothelia and enhances the surface sensitivity toward tumor cells.

The surface developed by the UIC research team demonstrated up to a million-fold increase in binding strength, and up to 7-fold increase in detection efficiency, as compared to the aEpCAM-coated PEG surface that is the current gold standard for circulating tumor cell detection.

Hong says this is the first study to capture the tumor cells on the surface exploiting the multivalent effect, which is most likely due to the spherical architecture of dendrimers. The research was selected as a "Hot Paper" by Angewandte Chemie and highlighted in Faculty of 1000 by Donald Tomalia, the inventor of PAMAM dendrimers.

The results demonstrate that the combination of nanotechnology and biomimicry has a "great potential to be applied for highly sensitive detection of rare tumor cells from blood," Hong said.

Source: University of Illinois at Chicago