Name the Attribute
Specify the molecule, impurity, structural feature, concentration range, and decision threshold.
Plan chromatography-based analytical work from the decision backward. This hub connects sample preparation, separation, detection, quantitation, structural identification, validation, and method lifecycle for proteins, conjugates, glycans, drug substances, and drug products.
Start with the Reportable Decision
Control the Sample
Map extraction, release, derivatization, adsorption, stability, and recovery before injection.
Protect Selectivity
Challenge critical pairs, matrix effects, load, detector response, and data processing.
Match Claim to Evidence
Use orthogonal detection, structural tools, standards, and validation appropriate to the claim.
Choose a Guide by Analytical Question
| Analytical question | Primary decision | Start here |
|---|---|---|
| Are soluble high-mass species real and how large are they? | Orthogonal aggregate interpretation | Aggregate methods |
| Has conjugation changed drug load, free payload, or size variants? | Connected ADC attribute panel | ADC attributes |
| Which glycans are present, where, and at what relative level? | Preparation and structural scope | Glycan workflows |
| Which process or degradation impurities require identification? | Risk-based impurity profile | Impurity profiling |
| Can a mutagenic impurity be controlled at the required level? | Matrix-specific sensitive method | Genotoxic impurities |
| How can a trace peak become structurally useful material? | Preparative impurity isolation | Impurity isolation |
| Which chiral condition supports analysis or isolation? | Stereoselective screening and scale-up | Chiral separation |
| Should content and related substances use one method? | Assay-versus-impurity framework | Assay vs impurities |
Match the denominator to the claim: area percent, molar mass, hydrodynamic radius, average DAR, relative glycan abundance, impurity concentration, enantiomeric purity, and assay content are not interchangeable results.
A Six-Step Analytical Evidence Path
Define intended useDevelopment, characterization, release, stability, comparability, or investigation.
Map analyte behaviorChemistry, stability, adsorption, matrix, response, and likely transformations.
Control preparationSampling, extraction or release, recovery, blanks, holds, and storage.
Build separationCritical pairs, loading, orthogonal selectivity, detector range, and carryover.
Confirm and quantifyStandards, response factors, structural evidence, uncertainty, and mass balance.
Validate and trendPerformance characteristics, robustness, system suitability, transfer, and lifecycle.
Core Guides in This Topic
Each guide uses a distinct analytical framework so methods reflect the physical or chemical attribute being measured.
SEC, SEC-MALS and DLS for Protein Aggregate Analysis
Distinguish chromatographic separation, absolute molar-mass measurement, and ensemble hydrodynamic screening in an orthogonal aggregate strategy.
ADC Characterization: DAR, Free Payload and Aggregates
Connect average DAR and drug-load distribution with free-payload, intact-mass, and aggregate evidence.
Glycan Analysis by Chromatography: Sample Preparation and Methods
Control release, labeling, cleanup, HILIC separation, site specificity, and structural confidence across glycan workflows.
Pharmaceutical Impurity Profiling: Detection and Identification
Build impurity profiles from process and degradation risk, then progress from detection to defensible structural identification.
Genotoxic Impurity Analysis: Planning a Sensitive Method
Translate a mutagenic-impurity control limit into a matrix-specific, sensitive method with recovery and carryover controls.
Isolating Pharmaceutical Impurities for Structural Characterization
Scale an analytical peak into an identity-preserving preparative isolation suitable for mass spectrometry and NMR.
Chiral Separation: Analytical Screening and Preparative Isolation
Screen chiral recognition broadly, then optimize load, fraction strategy, solvent recovery, and stereochemical stability.
Chromatographic Assay vs Impurity Testing: Choosing the Right Method
Decide whether assay and impurity testing can share a method without compromising either analytical target profile.
Methods and Evidence Roles
| Technique or evidence | Strongest role | Common overclaim to avoid |
|---|---|---|
| SEC and SEC-MALS | Size-based separation and peak molar mass | Treating all early-eluting material as stable aggregate |
| DLS | Rapid hydrodynamic screening in the unseparated sample | Reporting intensity distributions as mass-percent aggregate |
| LC or GC with MS | Sensitive detection and structural evidence | Assuming identical response or unique identity from mass alone |
| HILIC glycan profiling | Relative released-glycan distribution | Assigning unique linkage from retention and composition only |
| Preparative chromatography | Isolation for orthogonal characterization | Assuming the collected peak cannot transform |
| Chiral chromatography | Enantiomer separation and quantitation | Assigning absolute configuration from retention order |
Analysis Products and Services
Reading Paths by Development Stage
Biopharmaceutical Characterization
Begin with aggregate methods, ADC characterization, or glycan workflows. Use the assay framework to keep relative, absolute, and method-defined results clearly separated.
Small-Molecule Control
Move from impurity profiling to sensitive mutagenic-impurity methods or preparative isolation. Use chiral separation for stereochemical control and assay-versus-impurity decisions for routine method architecture.
Plan an analysis workflow around the decision
Share the molecule, matrix, attribute or impurity, concentration range, available standards, current method, and reportable need to frame a focused analytical plan.
References
- ICH. Q2(R2): Validation of Analytical Procedures. 2023; error correction 2025.
- ICH. Q14: Analytical Procedure Development. 2023.
- ICH. Q6B: Specifications—Test Procedures and Acceptance Criteria for Biotechnological/Biological Products.
