Whether it’s the hair loss, the nauseating fatigue, or the never-ending stream of pills, anyone who’s ever experienced cancer knows that treatment can be downright distressing. Traditional chemotherapy has a knack for attacking healthy cells in addition to the troublesome malignant ones, resulting in the aforementioned afflictions. But what if we could treat cancer without the debilitating side effects? What if we could target drugs at the offending cells only and release them precisely when we needed to?
Adah Almutairi, co-director of the Center for Excellence in Nanomedicine and Engineering at the University of California, San Diego (UCSD), has developed a technology involving light-activated nanoparticles that could potentially do just that. Using matter on the scale of 100nm, Almutairi and her research team placed drug molecules into tiny little balls she calls nanospheres. When administered for treatment, the drugs remain confined in their balls, unable to wreak their havoc on innocent, unsuspecting cells. Upon exposure to near-infrared light, however, the nanospheres break apart, releasing the contents within. The implications are crystal clear: if we can exercise control over exactly when and where drugs are needed, not only can drug uptake increase, side effects can be significantly reduced.
“We want these processes to work precisely, to minimize off-target drug effects,” Almutairi said.
But Almutairi’s invention isn’t unique in principle. In fact, targeted drug delivery has been at the forefront of research in the burgeoning field of nanomedicine for quite some time. Scientists first tried delivering drugs through liposomes, spherical vesicles that naturally assemble due to the properties of its constituent phospholipids.
“The problem with liposomes is that because they’re so biocompatible, they’re not very stable,” says Xiaosong Wang, a professor of nanotechnology at the University of Waterloo. “They dissociate easily, so they’re not very efficient for delivering drugs.”
Wang’s lab, which is located in the Waterloo Institute of Nanotechnology, conducts research on the self-assembly of metal-containing block copolymers – similar in essence to liposomes, but much more stable and much more varied. Magnetism, redox, and fluorescence are but a few of the fascinating properties inherent to metals that have exciting applications in medicine and beyond.
“There’s a lot of things you have to consider when applying these metal-containing polymers to drug delivery. The biggest issue is toxicity [or how it could potentially harm our bodies]. Then there’s biodegradability,” says Wang.
That’s where Almutairi’s model might have struck gold. Not only are her nanospheres “stable as a rock”, but they’re also perfectly safe. According to her, the nanospheres can “stay intact for a year before safely degrading,” as proven in animal trials with mice. The significance of that is monumental, demonstrating non-toxicity may be the first step in getting her invention on the market.
By creating stable, non-toxic, biodegradable materials, Almutairi’s research is treading new ground in efficient nano-based drug delivery, but it’s only the start. Nanotechnology is set for meteoric growth in the decades to come. As the field expands, research will improve on existing technologies, while innovative new ideas such as Almutairi’s will continue to be developed.
The pharmaceutical and health care industries will recognize the improved efficacy of nanomedicine (not to mention the profits), and will be chomping at the bit. Funding will increase. Clinical trials and patents will follow. Robert Langer, an MIT professor who pioneered targeted drug delivery, thinks there’s still a long way to go until these drugs saturate the market. If they do, though, nanotechnology will play a key role in the pharmaceuticals of our future.