Synthesis and characterization of a new type of chemically bonded liquid crystal stationary phase for HPLC

Two commercially available liquid crystals, 4-cyano-4'-n-pentyl-1,1'-biphen y and 4-cyano-4'-n-pentoxy-1,1'-bipheny, are bonded to a silica hydride sur face via hydrosilation in the presence of a free radical iniator, t-butyl p eroxide. Elemental analysis, diffuse reflectance Fourier transform infrared spectroscopy, and C-13 and Si-29 CP-MAS NMR spectroscopy ore used to confi rm the success of the bonding reaction. The C-13 CP-MAS spectra suggest a d ifference in the bonded phase morphology of the two materials. Static hydro lytic stability tests indicate these materials do not degrade significantly in both acidic and basic solutions. Chromatographic tests confirm that the se two bonded phase behave differently with respect to their retention of P AHs, alkyl-substituted benzenes and benzodiazepines.