Animal toxicity test of ND-silk films. Introducing (a) fully and (b) partially annealed films into the animal tissue. Degradation ability and non-inflammatory response of the (c) fully and (d) partially annealed films after two weeks of implantation. (e) A histological image of the examined tissue after implantation, showing no significant adverse effects in the subcutaneous adipose tissue surrounding the ND-silk implant. Credit: Biomedical Optics Express.
Nanodiamonds are a serious topic of investigation, potentially one day allowing for an unprecedented ability to track the activity of individual living cells within the body and to help to deliver medicines accurately to their targets. The nanodiamonds are purposefully made to be imperfect so that they fluoresce under applied light, but because of the rough edges on these flawed nanodiamonds, they often get stuck within the cellular membranes and fail to work as intended.
Now a collaboration of researchers from University of Melbourne, University of Sydney, and Tufts University has developed a way of coating these nanodiamonds with a layer of silk to help ferry the particles into the interior of cells. Because the silk used is transparent to visible and infrared light, it doesn’t negatively affect the imaging of the nanodiamonds, but its biocompatibility, flexibility, and biodegradability make it a highly effective material for use inside the body. Moreover, the researchers discovered that the silk’s own optical properties improve the brightness of the nanodiamonds by two to four times.
Looking towards the future, the team envisions silk to be used as a packaging material for targeted drug delivery. Because it can be made to dissolve at a predefined rate, we may one day see silk pouches being injected directly into the targeted tissue for long term release of drugs exactly where needed.
Paper in Biomedical Optics Express: Synthesis and characterization of biocompatible nanodiamond-silk hybrid material
More: A Silk Coat for Diamonds Makes Sleek New Imaging and Drug Delivery Tool…