Cell vital sign sensing

Nanodiamonds with high biocompatibility measure the condition of the body at the cellular level.

When a heteroelement is doped into a diamond crystal, the special structure created by the heteroelement causes the diamond to fluoresce. This special structure is called a color center, and there is no fluctuation or degradation in the emission intensity, as seen in other quantum dots and organic dyes, because of its structural stability. In recent years, Daicel’s detonation doping technology has been drawing attention in a variety of fields, and has made it possible to introduce a color center into the world’s smallest nanodiamonds. One example of this is fluorescent nanodiamonds doped with an Si atom. When exposed to 400-738 nm light, they emit red light centered around 738 nm. This light emission is stable and near infrared, which means it easily penetrates biological tissues and is advantageous for observation. In addition, Daicel offers cell vital sign sensing with Si-doped fluorescent nanodiamonds. The activity states of cells are measured by emitting light from nanodiamonds into specific cells within the body. As the name implies, nanodiamonds are diamonds and are chemically stable and highly biocompatible. Ultrasmall particles can be selectively introduced into targeted tissues, cells, or organelles by chemical or physical methods. Given this, Si-doped fluorescent nanodiamonds are expected to be used in vivo, such as for bioimaging and sensing.

Characteristics of fluorescent nanodiamonds

Si atom doped

• Near-infrared fluorescence is advantageous for observation from outside of the body
• Stable light emission without degradation
• Low toxicity, high biocompatibility
• Size that allows on-site measurement in a micro environment
• Fluorescent nanodiamonds with other fluorescent wavelengths are also under development