Peggy Sue

Two ways to get separation, identification and quantitation

Peggy Sue™ lets you separate and analyze proteins by size or charge from 2-440 kDa either by immunoassay or total protein. Got small sample volumes or starting materials? No problem. She uses as little as 0.2 µg/µL of protein in just 5 µL of sample, and runs up to 96 samples in one experiment. Charge ahead and do more with Peggy Sue!

Peggy Sue

How Can Peggy Sue Help You?

My sample is precious and I don't have enough for other methods

Sometimes you wish you could do more with your small and precious sample. Peggy Sue, our most frugal system can run up to 96 data points in one overnight run with as little as 5 µL of sample. And she can utilize that sample to the max by allowing you to interrogate those few microliters eight times, such as when analyzing an entire cell signaling pathway in a single run. Imagine all the data you can get from your sample!

Learn More

I need more than size data

Sometimes a band from a Western is not telling you the entire story about your target of interest. Size-based separation will not be able to resolve phosphorylation isoforms and other post-translational modification. A charge assay (cIEF plus immunodetection) has the power to let you see beyond what's detected by a traditional Western. Peggy Sue gives you two ways to get separation, identification and quantitation of your sample.

Learn More

I have too many samples and need higher throughput protein characterization

Our Simple Western systems offer the right throughput for your needs. Peggy Sue will process up to 96 data points per run in eight cycles of 12 data points each. Ideal for screening or applying the same assay to large number of samples. All the throughput you need with minimum hands-on time.

I am in a race to discover and I need my data faster

If analyzing 96 data points overnight is not impressive enough, maybe we should add that it includes data analysis. Set up and start your run in the afternoon and come back the next morning to find molecular weight (for size assay), charge isoform detection (charge assay) and signal quantification automatically calculated for each sample. If your time is as precious as your samples and you need results faster, we will help you win the race to discovery with Peggy Sue.

Click on the clock to see your time savings.

My current method is not reproducible

How reproducible will your current immunoassay be in analyzing 96 data points? With Peggy Sue you get intra- and inter-assay CV<20% for size and charge assays. How's that for reproducibility?

Simple Western Applications

Cancer &

Simple Western Instrument Cancer Research Applications


Simple Western Instrument SARS-CoV-2 Research Applications

Cell & Gene Therapy

Simple Western Instrument Cell & Gene Therapy Research Applications

Targeted Degradation

Targeted Degradation


SARS-CoV-2 Serology

SARS-CoV-2 Multi-Antigen Serology Module


Sample Required 0.3-1.2 µg lysate 0.6-1.2 µg 0.6-1.2 µg
Volume Required 3-5 µL/well 3-5 µL/well 5-12 µL/well
Size or pI Range Molecular weight (MW) ladders range from 2-440 kDa Molecular weight (MW) ladders range from 2-440 kDa Widest gradient ranges from pI 3 to pI 10
Sizing CV <10% <10% <10%
Intra-assay CV <15% <15% <20%
Inter-assay CV <20% <20% <20%
(± percent difference in MW)
± 15-20% for MW <20 kDa
± 10% for MW >20 kDa
± 15-20% for MW <20 kDa
± 10% for MW >20 kDa
± 0.1 pI units
Quantitation CV <20% <20% <20%
Dynamic Range 2-3 logs 3 logs 3 logs
Sensitivity ng Low pg Low pg
Capillary 5 cm, 100 µm, 400 nL