improving Nano-particle delivery

University of Toronto Engineering researchers have discovered a dose threshold that greatly increases the delivery of cancer-fighting drugs into a tumor.

"It's a very simple solution, adjusting the dosage, but the results are very powerful,"

Nanotechnology carriers are used to deliver drugs to cancer sites, which in turn can help a patient's response to treatment and reduce adverse side effects, such as hair loss and vomiting. However, in practice, few injected particles reach the tumor site.

In the Nature Reviews Materials paper, the team surveyed literature from the past decade and found that on median, only 0.7 percent of the chemotherapeutic nanoparticles make it into a targeted tumor

Chan's team saw the liver, which filters the blood, as the biggest barrier to nanoparticle drug delivery. They hypothesized that the liver would have an uptake rate threshold—in other words, once the organ becomes saturated with nanoparticles, it wouldn't be able to keep up with higher doses. Their solution was to manipulate the dose to overwhelm the organ's filtering Kupffer cells, which line the liver channels.

The researchers discovered that injecting a baseline of 1 trillion nanoparticles in mice, in vivo, was enough to overwhelm the cells so that they couldn't take up particles quick enough to keep up with the increased doses. The result is a 12 percent delivery efficiency to the tumor.

"In all of our studies, no matter how high we pushed the dosage, we never saw any signs of toxicity."

"There's a simplicity to this method and reveals that we don't have to redesign the nanoparticles to improve delivery," says Chan. "This could overcome a major delivery problem."

 

Nano-particle을 넣으면 주입한 양의 0.7%만 원하는 target tumor에 도달한다는 내용이다. 

그래서 사람들은 Nano-particle에 변화를 주고 그런 노력을 해왔는데, 

이 논문에서는 해결책으로 그냥 무식하게 때려박는 것을 솔루션으로 제시한다. 

신장이 barrier 역할을 하는데, 신장의 한계치 이상을 때려박으면 효율이 올라간다는 내용이다.

 

reference

Ben Ouyang et al, The dose threshold for nanoparticle tumor delivery, Nature Materials (2020). DOI: 10.1038/s41563-020-0755-z