In a report scheduled for the Sept. 12 issue of ACS’ Nano Letters, a monthly journal, they describe use of the coating to enable silica nanowires to enter cultured human cells and deliver a lethal dose of toxin.

Gregory Bohach, David McIlroy, Carolyn Hovde, and their colleagues point that nanowires and other nanomaterials (NMs), which are 50,000 times smaller in diameter than a human hair, have great potential as new drug delivery systems. NMs may penetrate tumors more easily, for instance, and could be coated with antibodies or other materials that home in on target cells while sparing normal cells.

One roadblock, however, involves finding ways to enable NMs to easily penetrate cells. The researchers report nanowires coated with the protein fibronectin penetrate cells more easily than uncoated nanowires. In experiments with human and animal cells, they showed that coated nanowires can enter and deliver a toxic agent called StxA1 that killed the cells. “This indicates that nanowires can carry StxA1 and potentially other toxic or therapeutic agents into cells,” the researchers said.-American Chemical Society