Imaged CIEF (iCIEF) is high resolution separation technique, in which proteins are separated based on surface charge that is related to the sequence and conformation. Chemical modifications of the protein sequence such as deamination of asparagine and glutamine residues or differences in glycosylation and amino acid clipping are reflected in CIEF peak pattern. This pattern can be used as a fingerprint method to identify that the correct form of the protein (including biologics and biosimilar) is being produced and that the purity of the protein is in the controlled range.
Identity and purity of therapeutic proteins are normally done rapidly (in about 10 minutes) through the use of an autosampler for unattended operation. Test samples are analyzed by CEInfinite in the presence of two pI markers. The iCIEF pattern obtained is compared to that of a reference sample under the same experimental conditions for protein identity confirmation. Other than chemical modifications, aggregation or fragmentation during protein production and processing will also be reflected in the peak pattern of iCIEF. Since CEInfinite provides robust, reliable separation and quantitation, the purity of protein can be also determined.
Measurement of protein activity can be done using protein interaction study with CEInfinite.
Working with a total solution provider, you not only have the CEInfinite for your routine protein assay, but also get the support from AES for your fast method development and characterization of the purity, identity, integrity and activity of your proteins.