Isoelectric Point (pI) Determination: characterization of your protein charge
The Isoelectric Point (pI) is a fundamental physicochemical parameter in the development of therapeutic proteins (monoclonal antibodies, enzymes, hormones). It correspond to the pH at which the net charge of the protein is zero.
Mastering the pI is necessary to ensure the stability, solubility, and biological activity of your biomolecules. Any variation in pI can reveal post-translational modifications (deamidation, sialylation, C-terminal lysine clipping) that directly impact the homogeneity and safety of your product.
FILAB laboratory supports you in the precise measurement of pI and the study of charge heterogeneity, in compliance with ICH Q6B guidelines.
Our isoelectric point analysis services
Isoelectric Point
Experimental pI measurement: Precise determination of the isoelectric point value for the protein of interest.
Charge heterogeneity profiling: Identification and quantification of acidic and basic variants (charge variants).
Stability and degradation studies: Monitoring pI evolution under stress conditions (temperature, pH, light).
Comparability studies: Assessment of biosimilarity between a reference product and a biosimilar candidate.
Our other biopharmaceutical analysis services
Identification and quantification of PTMs
Analysis according to ICH Q6B guideline
Analysis and localisation of disulfide bridges
Protein analysis using the following methods: BCA method, Lowry method, CBQCA method, Bradford method
Why choose FILAB ?
- Multidisciplinary expertise: a team of PhDs and engineers specializing in analytical chemistry and biochemistry.
- Dual chemistry / materials expertise
- ISO 17025 accreditation by COFRAC.
- 5,200 m² state-of-the-art analytical facility
- GMP environment
