From batch to continuous chromatographic purification of a therapeutic peptide through Multicolumn Countercurrent Solvent Gradient Purification (MCSGP)

A twin-column Multicolumn Countercurrent Solvent Gradient Purifica-tion (MCSGP) process has been developed for the purification of a ther-apeutic peptide, glucagon, from a crude synthetic mixture. This semi-continuous process uses two identical columns operating either in inter-connected or in batch mode, thus enabling the internal recycle of the por-tions of the eluting stream which do not comply with purity specifications.Because of this feature, which actually results in the simulated countercur-rent movement of the stationary phase with respect to the mobile one, theyield-purity trade-off typical of traditional batch preparative chromatog-raphy can be alleviated. Moreover, the purification process can be com-pletely automatized