High-performance liquid chromatography of amino acids, peptides and proteins. CXX. Evaluation of bandwidth behaviour of proteins chromatographed on tentacle-type anion exchangers

The dynamic behaviour of several proteins chromatographed on the Fractogel-TMAE and LiChrospher-TMAE tentacle-type anion exchangers was investigated through the analysis of experimental bandwidth data. Results were analysed by comparison of experimental data with bandwidth calculated on the basis of the protein assuming a rigid globular structure with a uniform interactive surface using the general plate height theory. The influence of the displacer salts NaCl and KBr and different mobile phase pH conditions (pH 5.5, 6.5, 7.5 and 9.6) on solute bandwidths were investigated. Very similar bandwidth dependencies were observed for all proteins separated on the Fractogel-TMAE sorbent with both displacer salt systems used. However, there was a marked difference in the bandwidth behaviour on the LiChrospher-TMAE sorbent with the two displacer salts. Furthermore, changes in the mobile phase pH resulted in significant differences in the dependence of the bandwidth ratios on both the gradient time and the type of displacer salt.