Synthesis and characterization of dibutyltetramethyldisilazane-bonded silica phases for reversed-phase high-performance liquid chromatography

Article abstract of DOI:10.1021/ac00017a035

A new silane, di-n-butyltetramethyldisilazane (DBTMDS), has been synthesized. Silanizations withh DBTMDS of a narrow-pore and a wide-pore silica yielded relatively high concentrations of bonded n-butyl ligands, of 4.22 and 4.09 μmol/m², respectively. The chromatographic properties of the n-butyl bonded phase (C₄-NH), synthesized with DBTMDS, were compared with n-butyl bonded phases (C₄-CL) synthesized with n-butyldimethylchlorosilane (BDMCS) and Vydac-C₄ under the same chromatographic conditions. The adsorption of basic compounds including N,N-diethylaniline (N,N-DEA), dansylarginine (Dns-Arg), and (phenyithio)hydantoin-arginine (PTH-Arg), as well as several polypeptides and small proteins including angiotensin I, angiotensin II, and lysozyme, was shown to be less for the C₄-NH sorbents than for C₄-CL and Vydac-C₄ sorbents. While the S value for the basic protein lysozyme was significantly lower on the wide-pore C₄-NH sorbent, the S and log k₀ values for a range of selected proteins were comparable to those obtained with the Vydac-C₄ sorbent. The tests of hydrolytic stability of the bonded phases showed significantly greater stability for the C₄-NH sorbents than for the C₄-CL sorbents under isocratic mobile-phase conditions of 10% and 40% acetonitrile with 0.1% TFA.