CASE STUDY
Optimizing a Therapeutic Peptide Purification Workflow with Sanitech Engineers' Systems
Challenge:
A pharmaceutical company was developing a synthetic therapeutic peptide (15 amino acids, 1.8 kDa) for clinical trials. The crude synthesis product, after cleavage and deprotection, yielded only 70% purity (by area percentage on analytical HPLC) and contained significant amounts of truncated sequences (10-12%), aggregate (5%), and residual protecting group by-products (8-10%). The initial 50 L batch size processing and target final purity of >98% presented significant scalability and purification challenges.
Solution implemented with Sanitech Engineers' Systems:
1. Pre-Purification and Concentration (Membrane Filtration)
Equipment
A Sanitech Engineers' pilot-scale Tangential Flow Filtration (TFF) System equipped with a suitable molecular weight cut-off (MWCO) ultrafiltration membrane.
Process
The 50 L crude peptide solution (at ~2 g/L concentration) can be initially concentrated 10-fold to 5 L using the TFF system or until the process flux is healthy. This step effectively removes high molecular weight aggregates and some large insoluble impurities. Subsequent diafiltration against 5 volumes of suitable buffer significantly reduced the initial salt content.
Result
This TFF step achieved a volume reduction of 90% and removed approximately 70% of the initial aggregate, increasing the peptide concentration to ~18 g/L. Peptide recovery during this stage can be >95%
2. Intermediate Purification (Ion Exchange Chromatography):
Equipment
A Sanitech Engineers' Preparative Ion Exchange Chromatography System with a 50mm to 800mm diameter x 1 to 1.5 m bed height anion/cation exchange resin column as required for the process based on the R&D.
Process
The concentrated peptide solution from TFF can be loaded onto the IEX column. A step gradient of increasing salt concentration (from 0 to 500 mM) in desired buffer can be used to elute the peptide, separating it from charged impurities like residual protecting groups and some truncated peptides.
Result
This step increased the peptide purity to 88%. The IEX column showed a dynamic binding capacity of few mg peptide/mL resin which may vary based on the resin used, processing few g of peptide per run.
3. Final Polishing (Reverse-Phase HPLC):
Equipment
A Sanitech Engineers' High-Performance Preparative HPLC System equipped with a 50 to 1000 mm diameter x 25 cm C18 or other suitable resin column packed with 10 µm media.
Process
The peptide fractions from the IEX step can be pooled and directly loaded onto the RP-HPLC system. A linear gradient of acetonitrile (ACN) or suitable solvent in water (both containing 0.1% TFA) from 15% to 45% solvent phase over 60 minutes can be employed.
Result
This final step can help in achieving the target purity. The main peptide peak can be collected, yielding a peptide purity of >98.5%. Each RP-HPLC run processed few g of peptide, with a typical run time of 90 minutes (including column equilibration and wash).
Overall Outcome:
Through this integrated purification workflow leveraging Sanitech Engineers’ advanced membrane filtration and preparative chromatography systems, the company can successfully purify more than desired quantity of therapeutic peptide per batch from an initial 50 L crude volume. The overall process achieved a desired purity and yield, significantly exceeding your initial expectations and enabling you to proceed confidently with clinical development. This case study demonstrates that Sanitech Engineers’ comprehensive solutions gives robust performance, scalability, and efficiency in this demanding pharmaceutical and other industrial application.