Nanoparticles (in red) being taken up in the brain of a live rat model with glioblastoma (in green).
Getting drugs into the brain by cloaking them within nanoparticles that can sneak through the blood-brain barrier has been the focus of a lot of nanotechnology research over the past few years. There’s quite a bit of progress toward that goal, including some notable successes. Because of this progress, scientists are coming to the realization that to achieve optimal results, the nanoparticles that reach the brain must also be discriminating enough to affect only the targeted types of cells. In reality, though, the same shell that cloaks drugs as they pass through the blood-brain barrier in many cases prevents the drugs from being absorbed by the cells in the brain.
Yale University scientists have been working on affecting the surface chemistry of poly(lactic acid) nanoparticles, a type that has been shown to be able to pass through the blood-brain barrier, in order to improve the uptake of the drugs within by brain cells. The investigators have discovered that attaching certain chemical bio-adhesive end-groups, specifically aldehydes, to the poly(lactic acid) nanoparticles makes the nanoparticles more prone to cellular uptake.
Aldehydes are attracted to amine, a compound found within many proteins, which in turn attracted the nanoparticles to reach the insides of cells. The Yale team also noted that tumor cells were particularly hungry for these new modified poly(lactic acid) nanoparticles, pointing toward an approach that will see more chemical tinkering to get the nanoparticles even more accurate in their targeting.
The team notes that increasing the uptake of the nanoparticles by cells should be evaluated in relation to the potential for increased overall toxicity by the nanoparticles.
Study in Nature Communications: Surface chemistry governs cellular tropism of nanoparticles in the brain…