We offer an end-to-end integrated protein manufacturing service thanks to our CDMO Xpress Biologics that have since 2014 continuously grown their capabilities to meet current demands to produce recombinant proteins and antibody fragments for preclinical and clinical use, specific to human and veterinary therapeutics, vaccines and diagnostics markets. Both, the production scale from 100 mg up to 40 g and the quality of the biologics from Research to HQ (High quality/ GLP) and GMP grade proposed by Xpress Biologics meet the quality requirements for in vitro, in vivo pre-clinical validation (proof-of-concept, early safety, potency, efficacy and toxicity studies) and clinical validation. 

Manufacturing services are based on four technological platforms 

  • Molecular biology platform: design of expression systems (E. coli & P. pastoris), 
  • Production yield optimization platform: fermentation development with 5L-scale fermenters  
  • Downstream process development platform: ie. extraction, clarification, liquid chromatography, tangential flow filtration 
  • Quality control platform: ie. HPLC, spectrophotometry 

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Molecular biology platform for rapid selection of Escherichia coli expression strains

The success rate of a new therapeutic or vaccine candidate depends not only on its efficiency vs side effects balance but also on its developability. The price and therefore the access of a new drug to the greatest number of patients are strongly related to the production yield and therefore to the ability of a strain to express a recombinant protein. The key parameter to ensure an efficient expression in Escherichia coli lies in the synchronization between the synthesis and secretion machineries. Xpress Biology set up a platform allowing the testing of different attributes impacting the synthesis and secretion efficiency such as the gene copy number, the transcription & translation strength as well as different secretion pathways.

Production yield optimization platform

Our optimization platform allows us to pinpoint the best fermentation conditions to ensure highest protein expression. The optimization platform includes a set of four identical stainless-steel fermenters (Biostat® C+, Sartorius) with a working volume of 5L, the ideal downscale model to ensure seamless scale-up to 50L-scale fermenter (Biostat® D-DCU, Sartorius).

Downstream process development platform

The strategy to purify a protein is based on the development of single capture chromatography followed by one polishing chromatography and one ultrafiltration step for the formulation of the purified protein.The choice between different types of chromatographic supports (anion and/or cation exchange and hydrophobic interaction sorbents) for the 1st and 2nd chromatographic steps will be based on the physico-chemical properties of the protein (hydrophobic profile, pI). A preliminary solubility trial will be performed in order to define the operating ranges (i.e. pH and salt concentrations) that can be applied during the purification development. The conditions of loading, washing and elution (protein load, buffer type, pH and salt concentration), for each matrix, will be then tested based on a Design of Experiment (DoE) approach performed using 96-well plates (static mode). The purity improvement, the host cell proteins (HCPs) removal, the recovery yield as well as the dynamic capacity will be determined with the selected conditions using 5mL-scale columns. Optimization and scalability will be finally performed with larger sized columns and bed heights compatible with industrial constraints.

Quality control platform

A rational approach is used to select the analytical tools adapted to verify process performance as well as to control the quality of the purified protein. For each step of the purification process, evaluation of the recovery yield (by UV and/or µBCA assay), purity improvement (by SDS-PAGE, WB and/or RP-HPLC), protein integrity (by RP-HPLC) and protein aggregation (by SE-HPLC) is implemented. The purified protein is characterized in terms of identity, purity/impurity, safety and biological activity using different analytical methods.

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