Properties of microdispersed sintered nanodiamonds as a stationary phase for normal phase high-performance liquid chromatography

The chromatographic properties of microdispersed sintered nanodiamonds (MSND) are studied under conditions of normal-phase HPLC. The retention characteristics of 30 substances representing four classes of aromatic compounds including monoalkylbenzenes, poly- methylbenzenes, di-n-alkyl phthalates and polyaromatic hydrocarbons in n-alkane mobile phases have been measured. The selectivity of MSND was compared with literature data for other common adsorbents including silica gel, alumina and porous graphitic carbon (PGC). MSND shows the distinctive adsorption properties especially in a stronger retention of aromatic hydrocarbons and in the better selectivity of the separation of geometric isomers. The significant improvement in separation efficiency up to 45300 theoretical plates per meter, was achieved for the first time for the columns packed with diamond related materials (DRM).