Suitability of teicoplanin-aglycone bonded stationary phase for simulated moving bed enantioseparation of racemic amino acids employing composition-constrained eluents.

The suitability of a teicoplanin-aglycone based chiral stationary phase for the simulated moving bed (SMB) enantioseparation of amino acids under enzyme-compatible conditions was shown following a procedure that is based solely on model-based simulations and HPLC experiments. A set of eight amino acids could be separated employing aqueous solvent containing only 10% (v/v) methanol, five of them with baseline resolution. The impact of type and concentration of organic modifier and pH modifier and pH on the separation characteristics of racemic methionine was investigated. Invariant elution profiles of repetitive adsorption/desorption of large amounts of methionine representing SMB-like conditions suggest stable adsorption behavior. Competitive loading capacity (20 mg of methionine per g of chiral stationary phase (CSP)) and SMB productivity (1 g of D-methionine per g of CSP per day) were predicted. The applied transport-dispersive model based on a competitive Bi-Langmuir isotherm was validated and its parameter estimated by model-based experimental analysis.