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Catalog # 004-650 | ProteinSimple a Bio-Techne Brand
Jess Simple Western System
I need to do protein normalization

Your Complete Protein Analysis Solution

Jess automates the protein separation and immunodetection of traditional Western blotting, eliminating many of the tedious, error-prone steps. Just load your samples and reagents into the microplate and Jess separates your proteins by size, and precisely manages antibody additions, incubations, washes and even the detection steps. Come back to fully analyzed results in 3 hours. Go further with high sensitivity multiplexing—her best-in-class fluorescent detection channels and RePlexing capabilities get you all the information you need on your samples in one run. Jess automated western blot system—she's like multiplexed Western blot meets ELISA in one.

ReThink, ReUse, RePlex!

RePlex™ feature on Jess enables you to run two immunoassays within the same capillary to get more rich protein characterization data from just one sample. - Quantify expressed phosphorylated target and total target levels. - Normalize your data with total protein expression data in the same capillary. - Save time and money on consumables.

Market leading fluorescence sensitivity: Stellar NIR / IR Modules for Jess

Stellar NIR / IR modules for Jess set the standard for fluorescence Western blotting detection sensitivity. With Stellar modules, low abundance proteins can be detected, and multiple targets can be multiplexed in the same sample using multi-color fluorescence channels. Plus, use the Stellar Total Protein assay to normalize your multiplexed results to total protein abundance within the same lane.

Industry-leading NIR/IR fluorescence detection sensitivity with Stellar

Learn more about the benefits of Stellar NIR / IR modules and see how they compare to other detection methods.

  Jess with Chemiluminescence Jess with Stellar NIR Jess with Stellar IR Competing Fluorescence Western Blotting Technology

LOD of

RNase A

1.1 pg 0.4 pg 0.7 pg >50 pg

LOD Comparison of Stellar NIR / IR, Chemiluminescence, and Leading Competitor for Fluorescence Western Blotting using RNase A as the target (Learn more).

Citations for Jess

View all citations for the Simple Western platform.
Please visit our Instrument Citation Database to search our collection of scientific articles that feature our instruments.

Testimonials from your Peers for Simple Western

Showing  1 - 5 of 31 testimonials Showing All

"Using Simple Western has been extremely rewarding, especially due to how easy it was to transfer our western blotting assays to a fully automated format on Simple Western and how well CST antibodies perform on the platform."

Chris LaBreck, Ph.D., Senior Product Scientist, Cell Signaling Technology (CST)

"Simple Western™ allows us to run three-hour assays, which would usually take us two days with traditional Western blots."

Laura Martins, Ph.D., Early Development Scientist, Oxford Biomedica

"Jess allows us to immediately identify potential autophagy biomarkers as they are upregulated or downregulated in response to treatment. This allows us to use more advanced statistical techniques such as principal component analysis and hierarchal clustering to recognize key correlations in our research with ease"

John K. Blackwood PhD, Head of Biology, and Jakub Stefaniak PhD, Samsara Therapeutics

"The introduction of an Abby will enable us to answer important questions quicker, such as identifying the disease driving mechanism and molecules surrounding osteoarthritis. Moving away from the tedious manual western blotting process, which can take up to two days, and introducing automation will speed up time to data and provide increased sensitivity and accuracy."

Dr. Mario Rothbauer, Postdoc Researcher, Department of Orthopedics and Trauma Surgery, Medical University of Vienna

"It can be difficult to optimize new antibodies, particularly for brain markers where you have a lot of background noise and low levels of your target. The appropriate control and low variability between plates using Simple Western™ means we can complete our studies in weeks rather than months."

Dr. Michael Harte, Senior Lecturer in Drug Action, Neuroscience, University of Manchester

Showing  1 - 5 of 31 testimonials Showing All

More Information About Jess

How Does Jess Work?

Simple Western assays are automated, capillary-based immunoassays that solve many of the challenges that come with traditional Westerns. All assay steps from protein separation, immunoprobing, detection, and analysis are fully automated. The variability in the manual processes that impact reproducibility, quantitation, time to result, and overall data reliability is eliminated. Best of all, the transition is simple—the same antibodies you use for Western blotting protocols can be used with Simple Western assays.

Your sample, separation matrix, stacking matrix, antibodies, and reagents are loaded automatically from a specially designed plate. Jess begins by aspirating the separation matrix and then the stacking matrix into each capillary. Next, your sample is loaded, and capillaries are lowered to make contact with running buffer. Voltage is applied to enable separation by molecular weight. Once the separation is complete, UV light immobilizes the proteins to the capillary wall. With proteins now immobilized and the matrix cleared of the capillary, Jess starts the immunoprobing process. In just 3 hours you'll have quantitative, size-based data ready for analysis.

Jess gives you four different ways to analyze proteins:

  1. Multiplex detection: Maximize your time and sample, and get the information you need in one shot by multiplexing in chemiluminescence and infrared (IR) and near-infrared (NIR) fluorescence channels. The Stellar™ NIR/IR Modules bring industry-leading fluorescence detection sensitivity for Western workflows. Take multiplexing even further with Superplex to assay in chemiluminescence and 2-color fluorescence with Protein Normalization at the same time.
  2. RePlex™: Why bother stripping and reprobing? RePlex lets you run two immunoassays within the same capillary to get all your rich protein characterization data from just one sample!
  3. Protein Normalization: Jess gives you an easy way to see if your samples contain a consistent protein load—just load the Protein Normalization reagent into the assay plate and Jess will take care of the rest. Jess's proprietary fluorescent reagent measures proteins immobilized in the same capillary as your immunoassay. You can effectively normalize expression of your target protein to get accurate and consistent data, giving you confidence in your results. And with Superplex you can assay in chemiluminescence and 2-color fluorescence on top of Protein Normalization.
  4. Blot imaging: Still doing traditional Westerns? You can image chemiluminescence Western blot with Jess's built-in blot imaging system.

What does the data look like? At the end of the run, Simple Western data are processed automatically in Compass for Simple Western. Simple Western data are displayed by lane in a virtual blot-like image similar to traditional Western blot results. If you're more familiar with capillary electrophoresis, you can see your results in a more traditional electropherogram view too. Quantitative results such as molecular weight, signal intensity (area), % area, and signal-to-noise for each immunodetected protein are presented in the results table automatically.

Jess Applications

Cancer & Immuno-Oncology



Transform your cancer & immuno-oncology research by utilizing next-generation Western blotting tools to give you richer views into your samples.

Solutions for Cell Signaling and Signal Pathways Analysis

Cell Signaling


Analyze entire signaling pathways with high sensitivity multiplexing and total protein normalization.

Testing for Lentivirus and AAVs

Cell and Gene Therapy


Next-generation analytical instrumentation to help improve and accelerate your cell and gene therapy workflows.

Advances in Targeted Protein Degradation

Targeted Degradation


Boost your screening studies using high throughput & hands-free Simple Western systems for quantitative analysis.

Biosimilar Antibodies Teaser Image

Pharmacokinetic Analysis


High-throughput pharmacokinetic analysis with quantitative, high-sensitivity assays directly in complex lysates and tissue homogenates. 




A validated workflow for protein analysis in extracellular vesicle samples from the leaders in exosome isolation and high sensitivity Western blotting solutions.

Vaccine development image

Vaccine Development


Improve reproducibility, quantitation, and time to market for your vaccine candidates.

Neuroscience App image for Ella



Increase your sensitivity and multiplexing capabilities with neural samples using automated Western blotting systems.

Simple Plex HEK-HCP Assay

Bioprocess Impurities


Screen for processing-related impurities and host-cell related contaminants. Quantify empty/full capsid content of viral vectors like AAVs.


SARS-CoV-2 Research


Reduce your lab time while accelerating your COVID‑19 research. Set up, leave and remotely review your data in just 3 hours!

Description Total Protein Specification Chemiluminescence and Stellar Fluorescence Specification Classic Fluorescence Specification Protein Normalization Specification
Sample required 0.3-1.2 µg 0.6-1.2 µg 2-4 µg 0.6-4 µg
Volume required 3 µL/well
Size range Molecular weight (MW) ladder ranges from 2-440 kDa
Sizing CV <10%
Intra-assay CV <15% <20%
Inter-assay CV <20%* <20%**
Resolution (± percent difference in MW) ± 15-20% for MW <20 kDA
± 10% for MW >20 kDa
Quantitation CV <20% (total protein, chemiluminescence and fluorescence) N/A
Dynamic range 2-3 logs 3-4 logs 1 logs
Sensitivity ng Low pg High pg ng
Capillary 5 cm, 100 µm, 400 nL
Runtime <3 hours <4 hours with immunoassay
Samples per run 13 or 25
Weight 23 kg
Dimensions (closed) 0.36 m H X 0.3 m W X 0.57 m D
Dimensions (open) 0.36 m H x 0.53 m W x 0.57 m D
Power US/CAN 120 V AC, 60 hz, 4.2 amps
Europe 240 AC, 50 Hz, 2.1 amps
Japan 100 AC, 50/60 Hz, 5.0 amps
Operating temperature 18-24 °C
Operating humidity 20-60% relative, non-condensing
* inter-assay CV is with system control
** percent peak area