L4-2286 — Annual report 2009
1.
Process for the purification and/or isolation of biologically active granulocyte colony stimulating factor

A process for isolation of biologically active G-CSF is disclosed, enabling the separation of correctly folded biologically active monomeric G-CSF from the incorrectly folded, biologically inactive monomeric, oligo- or polymeric and also from aggregated molecules of G-CSF using affinity chromatography IMAC. The process can be advantageously performed under native conditions. Only 2 additional chromatographic steps, CEX and SEC, are needed for polishing. The process results in the high-yield of G-CSF with a purity of greater than 99% and is particularly suitable for industrial production.

COBISS.SI-ID: 4156698
2.
Correlations between in vitro potency of polyethylene glycol-protein conjugates and their chromatographic behaviour

Pegylation is an efficient methodology for half-life extension of proteins. Most of the positive pharmacological effects are usually ascribed to increased molecular size. To explore the impact of PEG on in vitro potency, a series of well-defined conjugates of IFN were prepared with PEGs of different lengths and shapes attached to the N-terminus of the protein. Beside of the expected impact of increased molecular size, the studies revealed high correlation between in vitro potency and chromatographic behavior on CEC, both methods reflecting the protein masking effect by the attached PEG moiety.

COBISS.SI-ID: 4143898