Nanodiamonds, being nothing but carbon, are quite biocompatible, but they’re difficult to work with since they’re non-reactive and won’t bind to most things. By coating Nanodiamonds with a polymer based on the serum albumin protein, the compound can be made to bind to Drugs and is readily absorbed through the Blood-Brain barrier.
To make the Nanodiamonds useful for brain imaging, the team had single-atom defects created within by replacing a carbon atom with one of nitrogen. This made the tiny diamonds flicker radically when exposed to laser light, but it also made the Nanodiamonds visible on MRI scans.
The technique has already been tested in lab mice, without any noticeable damage to the blood brain barrier, but the technology is still in the very early stages and there’s a lot of work left before we’ll be using Nanodiamonds for neuro applications in the clinical space.