Fast-Track Your PK Analysis with Automated Capillary Immunoassays
Simple Western™ is a fully automated capillary immunoassay. Separate proteins by capillary isoelectric focusing (cIEF) or capillary electrophoresis sodium dodecyl sulfate (CE-SDS) followed seamlessly by immunodetection directly in the capillary.
Reproducible quantification. Use CE-SDS to resolve proteins by size and quantify intact IgG, aggregates and fragments IC/EC50, LOD, LOQ, and more, with intra- and inter-assay CVs of <20%.
Add a Size- or Charge-base separation to your immunoassay. Use CE-SDS to resolve proteins by size and quantify intact IgG, aggregates and fragments. Use cIEF to quantify the main peak, acidic peak(s), and basic peak(s) of your antibody therapeutic.
No sample cleanup. Analyze highly complex samples like human serum without lengthy purification or concentration steps.
High throughput. Process up to 96 samples in one overnight run without user intervention.
High sensitivity. Highly sensitive immunodetection using as little as 3 µL of sample. Get up to 8 data points on the same 5 µL of sample. Multiplex to get more data points per sample with chemiluminescence and Stellar™ NIR/IR fluorescence detection with industry-leading sensitivity. Use RePlex™ to perform sequential immunoassays or Total Protein Detection on the same sample.
3-4 log dynamic range. Larger than ELISA.

Simple Western Combines CE-SDS / cIEF with Immunodetection
ELISA | CE-SDS | cIEF | Simple Western | |
---|---|---|---|---|
Immunodetection | Yes | No | No | Yes |
Charge separation | No | No | Yes | Yes |
Size separation | No | Yes | No | Yes |
Quantitative Protein Characterization in Complex Samples
Simple Western on Peggy Sue™ combines the separation power of cIEF and CE-SDS assays with the sensitive and specific detection of an immunoassay. This combination places Simple Western in a unique position to study the PK properties of therapeutic monoclonal antibodies and their biosimilars.
Minimal matrix effects. Following cIEF/CE-SDS separation, proteins are immobilized to the capillary and thoroughly washed prior to immunodetection, flushing the remaining sample matrix out of the capillary. Thus, immuno-probing on Simple Western occurs in an idealized environment rather than within the sample matrix environment, reducing matrix interference that can plague ELISAs while also providing high-resolution charge/size separation.
Sensitive immunodetection. Detect small amounts (low pg) of target protein with conventional Western blot antibodies.
Upstream and downstream workflows. Obtain comparable charge separation profiles in crude samples from early stages of product development with Peggy Sue and later stages of purified samples with Maurice cIEF. For more information, refer to our Protocol on Method Transfer between Maurice and Peggy Sue.
In this Application Note, Simple Western Charge and Size assays provided a complete picture of the PK activity of adalimumab in human serum. The Simple Western Charge assay provided the most wealth of information and was able to detect significant changes in the drug profiles over the course of the study, including the detection of unexpected stress-associated acidic peaks.
Bioprocess Workflow Solutions from Start to Finish
Look to us to provide top-quality instrumentation, reagents, and services for your protein bioprocessing. We offer an outstanding product selection and the flexibility to meet your specifications.
Take advantage of our:
- Decades of experience in process development for cell culture and protein purification.
- World class reagent and assay development.
- Industry preferred technologies that simplify, automate, and advance protein analysis.
- Proven record of customer satisfaction for bulk supply, custom solutions, and documentation.
- Compliance with 21 CFR Part 11, ISO 13485:2016, USP <1043>, 21 CFR 820, and ISO 9001:2015 as applicable.
- Absolute confidentiality
