“Would you poison the entire garden to kill one weed?” asked Justin Hanes at the opening of his talk at the 2012 Johns Hopkins annual NanoBio Symposium. “Unfortunately, that is how most chemotherapy works today.” Hanes is a professor of ophthalmology at Johns Hopkins School of Medicine and an affiliated faculty member of the Institute for NanoBioTechnology.

On average, less than one percent of any chemotherapy cancer treatment will go to a patient’s tumor. The remaining 99 percent circulates through the rest of the patient’s body, kills healthy cells unnecessarily, and causes often unbearable side effects. This alarming statistic has led Hanes and his team to focus on targeted, chemotherapeutic drug delivery using nanoparticles.

Hanes explained that nanoparticles are ideal in cancer treatment because tumors form new blood vessels within themselves to be able to receive nutrients, and these tumor-associated blood vessels are leaky. Thin, leaky blood vessel walls are ideal for drug-loaded nanoparticles, which are on the order of 1-100 nanometers in diameter, to break through to reach tumor cells. The ultimate goal of nanoparticle drug delivery for cancer is to synthesize bio-targeted particles that provide localized delivery straight to the tumor alone, improving drug effectiveness and reducing undesirable side effects.