Characterization of Novel Reversed-Phase HPLC Packings Based on Hybrid Organic/Inorganic Particles

Library Number:
Part Number:
Tom Walter;Bonnie Alden;Ray Fisk;Christina Gendreau;Pamela Iraneta
PittCon 200; New Orleans; 15 March 2000
Content Type:
Content Subtype:
Other Symposium
Uracil; Naphthalene; Acenaphthene; Butyl Paraben; Amitriptyline; Propranolol; Nicotine; Methamphetamine; Amphetamine; Ibuprofen; Benzoic Acid; Salicylic Acid; Lidocaine; Doxepin; Imipramine; Nortriptyline
XTerra MS C18 5 µm Steel 3.9 mm 150 mm XTerra RP18 5 µm Steel 3.9 mm 150 mm
Despite significant advances in the technology of silica-based reversed phase HPLC packings over the last decade, current materials still suffer from limited stability in alkaline and strongly acidic mobile phases. To address this shortcoming, we have developed a new family of reversed-phase packings based on hybrid organic-inorganic particles having the composition SiO2(CH3SiO1.5)0.5. We attribute the improved performance of these materials to their reduced concentration of residual silanols and thorough coverage with organic groups. We have evaluated the stability of columns containing these new packings under both acidic and basic conditions, and compared the results to those obtained for conventional silica-based C18 columns. For C18-bonded hybrid columns we observe a striking improvement in lifetime under alkaline conditions; conditions where column failure is due to hydrolytic dissolution of the particles. In addition, the unbonded hybrid particles are exceptionally stable to acids, with no change in carbon content after heating in the presence of 1 M HCl at 95ºC for 24 hrs. These results will be discussed, along with preliminary results for new hybrid particle compositions.

Title Format File Size
tw_pc00l PDF 79.45kB