Deagglomeration and characterization of detonation nanodiamonds for biomedical applications

Detonation nanodiamonds (DNDs) are usually small particles of 4–5 nm, but in aqueous suspension, DNDs form agglomerates in sizes larger than 1 μm. We propose the use of Bead Assisted Sonic Disintegration and a carboxylation procedure, to reduce DNDs aggregates sizes to approximately 100 nm. High cost zirconium beads have been substituted by silica beads synthetized in our laboratory and less-time consuming conditions were standardized. Techniques as Dynamic Light Scattering (DLS), Fourier Transform InfraRed Spectroscopy (FTIR), Transmission Electron Microscopy (TEM) and X-ray Photoelectron Spectroscopy (XPS), have been used to characterize the resulting diamond nanoparticles. While the incubation of Red Blood Cells with partially disaggregated DNDs was used to study whether these nanodiamonds impact in a living system. Our results show the absence of a negative effect in cell viability as well as no differences between Raman spectra of hemoglobin (Hb), from control and cell + DNDs conditions.