Direct sector field ICP-MS determination of metal impurities in detonation nanodiamond

A simple, rapid, sensitive and accurate method for the determination of metal impurities in detonation nanodiamond (DND), based upon the direct aspiration of aqueous suspensions of nanodiamond into a sector field inductively coupled plasma mass spectrometer (ICP-MS) is proposed. Quantitative release, atomisation and ionisation of the nanodiamond coated and encased elements, within the plasma, and their detection free from spectral interference, was confirmed by comparing results obtained from the direct ICP-MS analysis of aqueous suspensions with results from the ICP-MS analysis of the acidic digests of pre-ashed DND, obtained through DND combustion in air at 723 K for 48 h. The developed direct method was capable of the quantification of more than 30 elements at concentration levels of 10−8 wt.%, with acceptable levels of precision and accuracy, from an aqueous suspension of just 0.1 mg mL−1 DND.