Available analytical methods

celares has established a comprehensive set of analytical methods for the characterization of bioconjugates and chemical polymers that are used as active pharmaceutical ingredients (APIs) or excipients in pharmaceutical preparations.

Celares GmbH
Alliance coupled to CAD

Our currently available methods include:

ParameterMethodBioconjugatePolymerGMP
Product characterization
Absolute MW,
polymer : protein ratio
SEC-UV-RI-MALLS
MW, PDI, purity, contentSEC-RI / GPC-RI
Absolute MW, degree of modificationMALDI-ToF-MS, LC-ESI-MS
Structural integrityNMR
Potency, enzymatic activityColorimetric assays, UV-VIS methods in well-plate format
Identity, PTMs, PEGylation sitesLC-MS-based peptide mapping

Extinction coefficientAmino acid analysis
Content and concentrationUV/VIS spectroscopy, BCA assay, chromatographic methods
Terminal activityRP-HPLC
Product related impurities / degradation products

Purity, Identity, structural integrity
SDS-PAGE followed by
– Coomassie staining
– Titrisol staining
– Western-Blotting









IdentityELISA

Purity, impurity profileSE-LC & HPLC, UPLC
Isoforms, oxidated / deaminated species, aggregatesUPLC/HPLC in combination with RP, SEC or IEX methodology
Process related impurities or additives
BHTRP-UPLC
CyanideColorimetric assay
NHSRP-HPLC
PEGRP-UPLC/HPLC with ELS or CA detection
Polymers in protein solutionsSE-UPLC-ELSD, RP-UPLC-ELSD

Polysorbate 20 / 80RP-HPLC-ELSD or CAD

Bioanalytics (in biological samples)
Anti-drug antibodiesELISA / Western blotting

Amino acid levelsRP-HPLC with pre-column derivatization

Bioconjugate levelELISA, HPLC

Degradation productsWestern blotting, HPLC
General and generic methods
Conductivity and pHConductometry, potentiometry
OsmolalityFreeze point osmometry
Appearance, color, clarityVisual inspection
TurbidityNephelometry
Water contentKarl-Fischer titration

Celares is constantly extending its analytical methods portfolio. If your analytical need is not listed above, we are happy to develop a new method specifically for your purpose.

Contact partner

Dr. Christoph Radcke

Dr. Christoph Radcke
Head of Analytics and QC

+49 30  9489 2350

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+49 (0) 30 94892350

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