Boosting nanodiamond fluorescence: towards development of brighter probes

Abstract

A novel approach for preparation of ultra-bright fluorescent nanodiamonds (fNDs) was developed and the thermal and kinetic optimum of NV center formation was identified. Combined with a new oxidation method, this approach enabled preparation of particles that were roughly one order of magnitude brighter than particles prepared with commonly used procedures.

Nanodiamonds: From Synthesis and Purification to Deposition Techniques, Hybrids Fabrication and Applications

“…Another gas phase purification can be performed via plasma treatments. The effect of an oxygen plasma was found very similar to air annealing in terms of oxidation state [43].…”

“…As a consequence, detonation NDs can be rapidly etched for temperature higher than 430°C [61]. For bigger HPHT NDs (45 and 140 nm), an air oxidation was optimized at 510°C [43]. A monitoring of carbon and oxygen K-edge X-ray absorption allowed a fine characterization of surface modifications for temperatures included between 475 and 575°C [62].…”

“…For this purpose, different hot acid mixtures were used: HF/HNO 3 [26], successive HCl and H 2 SO 4 /HNO 3 /HClO 4 [27], successive H 2 SO 4 / HNO 3 and HCl [33,42]. In addition to oxidation, an annealing of HPHT NDs carried out in melted KNO 3 at 560°C [43] was very efficient to produce rounded NDs as shown by TEM (Fig. 9).…”

“…3a [26]. Moreover, starting from HPHT NDs, an oxidation treatment using melted potassium nitrate (KNO 3 at 560°C) was powerful to round up corners and edges [43].…”

Recent Developments and Applications of Nanodiamonds as Versatile Bioimaging Agents

“…30,31 Several studies have employed centrifugation techniques to select smaller ND particles, followed by electron or ion bombardment and annealing. 25,[30][31][32][33] FNDs as small as 10 nm have been fabricated with detonation NDs, but the efficiency of the color center formation was low 33 and their photostability was poor. 34 Boudou et al, 35 on the other hand, have taken a different approach to produce FNDs containing NV -centers.…”