SHAPE SELECTIVITY OF POLYCYCLIC AROMATIC-HYDROCARBONS AND FULLERENES WITH TRI-TERT-BUTYLPHENOXY BONDED SILICA PHASE IN MICROCOLUMN LIQUID-CHROMATOGRAPHY

Retention behaviors of various planar and non-planar polycyclic aromat ic hydrocarbons (PAHs), and all carbon compounds so-called fullerenes with 2,4,6-(tri-tert-butylphenoxy)dimethyl (TBP) silica phase and benz yldimethyl (Benzyl) silica phase have been investigated using microcol umn liquid chromatography system. The results clearly indicate that th ese phases possess a ''non-planarity'' recognition capability of PAHs. Non-planar solutes were retained longer than planar ones with these p hases under certain separation conditions, although the opposite trend where the planar solutes are retained longer than the non-planar ones was observed with typical octadecylsilica (ODS) phases. This unique b ehavior can be explained by the specific molecular-molecular interacti on between non-planar solutes and the stationary phase moiety having a cavity like structure made by the three tert-butyls and phenyl ring o f the moiety, The separation of C-60 and C-70 were also examined and t he difference of the structural uniqueness between TBP phase and Benzy l phase showed interesting results for such bulky fullerenes separatio n.