New nanomedicines may better target tumors.

Nanotechnology has made a major impact on industry, leading to, for example, batteries that store more energy and solar cell coatings that absorb more light. In theory, scientists can also engineer nanoparticles that carry drug payloads, avoid healthy tissue, and seek out tumors. “The concept is really beautiful: A drug loaded into a nanoparticle will destroy the tumor with no side effects,” says Warren Chan, PhD, a biomedical engineer at the University of Toronto in Canada. At this point, however, it’s mostly still a concept. “A limited number of nanomedicines have gone through clinical trials,” he says. Now researchers are trying to apply lessons learned over the past few decades to develop therapies that better target tumors. The key is to go beyond relying on size alone, as in the early days of nanomedicine, and specifi cally engineer therapies for a particular clinical purpose, says Dean Ho, MS, PhD, a bioengineer at the University of California, Los Angeles.