EasySep™ Direct Human CTC Enrichment Kit

Immunomagnetic negative selection from whole blood kit
EasySep™ Direct Human CTC Enrichment Kit

Immunomagnetic isolation of circulating tumor cells directly from whole blood

100 mL whole blood
Catalog # 19657
903 USD
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Required Products
  1. EasySep™ Magnet
    EasySep™ Magnet

    Magnet for column-free immunomagnetic separation

  2. D-PBS Without Ca++ and Mg++
    D-PBS (Without Ca++ and Mg++)

    Dulbecco’s phosphate-buffered saline without calcium and magnesium


The EasySep™ Direct Human CTC Enrichment Kit can be used to enrich Circulating Tumor Cells (CTCs) directly from human whole blood by immunomagnetic negative selection without the need for either density gradient centrifugation or RBC lysis. Isolated cells are immediately ready for downstream analysis or assays.
• > 99.9% RBC depletion without the need for density gradient centrifugation, sedimentation, or lysis
• Up to 3 log depletion of normal hematopoietic cells
• Fast, easy-to-use and column-free
• Isolated cells are untouched
  • EasySep™ Direct Human CTC Enrichment Kit (Catalog #19657)
    • EasySep™ Direct Human CTC Enrichment Cocktail, 2 x 2.5 mL
    • EasySep™ Direct RapidSpheres™, 4 x 2.5 mL
Magnet Compatibility
• EasySep™ Magnet (Catalog #18000)
• “The Big Easy” EasySep™ Magnet (Catalog #18001)
• Easy 50 EasySep™ Magnet (Catalog #18002)
• EasyEights™ EasySep™ Magnet (Catalog #18103)
Cell Isolation Kits
Cell Type
Cancer Cells and Cell Lines
Sample Source
Whole Blood
Selection Method
Cell Isolation
Area of Interest
Cancer Research, Immunology

Related Products

Labeling Antibodies

Scientific Resources

Product Documentation

Document Type Product Name Catalog # Lot # Language
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Product Information Sheet
Product Name
EasySep™ Direct Human CTC Enrichment Kit
Catalog #
Lot #
Document Type
Safety Data Sheet 1
Product Name
EasySep™ Direct Human CTC Enrichment Kit
Catalog #
Lot #
Document Type
Safety Data Sheet 2
Product Name
EasySep™ Direct Human CTC Enrichment Kit
Catalog #
Lot #

Educational Materials(11)

EasySep™ Cell Separation Technology
Tools for Cancer Research
EasySep™ Direct: Cell Isolation from Whole Blood in 20 Minutes
Isolation of Circulating Tumor Cells
Human Immune Cytokines
How to Isolate Cells Directly from Whole Blood Using the EasySep™ Purple/Silver Magnets
Simultaneous Cell Isolation from Multiple Samples Using the EasyEights™ EasySep™ Magnet
Cell Isolation Directly from Whole Blood without RBC Lysis or Centrifugation: EasySep™ Direct
How to Isolate Cells Directly from Whole Blood Using the Easy 50 EasySep™ Magnet: 30-Minute Protocol
How to Isolate Cells Directly from Whole Blood - EasySep™ Direct Protocol, EasyEights Magnet
Scientific Poster
Unbiased Enrichment of Circulating Tumour Cells Directly from Whole Blood

Frequently Asked Question

Can EasySep™ be used for either positive or negative selection?

Yes. The EasySep™ kits use either a negative selection approach by targeting and removing unwanted cells or a positive selection approach targeting desired cells. Depletion kits are also available for the removal of cells with a specific undesired marker (e.g. GlyA).

How does the separation work?

Magnetic particles are crosslinked to cells using Tetrameric Antibody Complexes (TAC). When placed in the EasySep™ Magnet, labeled cells migrate to the wall of the tube. The unlabeled cells are then poured off into a separate fraction.

Which columns do I use?

The EasySep™ procedure is column-free. That's right - no columns!

How can I analyze the purity of my enriched sample?

The Product Information Sheet provided with each EasySep™ kit contains detailed staining information.

Can EasySep™ separations be automated?

Yes. RoboSep™, the fully automated cell separator, automates all EasySep™ labeling and cell separation steps.

Can EasySep™ be used to isolate rare cells?

Yes. We recommend a cell concentration of 2x108 cells/mL and a minimum working volume of 100 µL. Samples containing 2x107 cells or fewer should be suspended in 100 µL of buffer.

Are the EasySep™ magnetic particles FACS-compatible?

Yes, the EasySep™ particles are flow cytometry-compatible, as they are very uniform in size and about 5000X smaller than other commercially available magnetic beads used with column-free systems.

Can the EasySep™ magnetic particles be removed after enrichment?

No, but due to the small size of these particles, they will not interfere with downstream applications.

Can I alter the separation time in the magnet?

Yes; however, this may impact the kit's performance. The provided EasySep™ protocols have already been optimized to balance purity, recovery and time spent on the isolation.

For positive selection, can I perform more than 3 separations to increase purity?

Yes, the purity of targeted cells will increase with additional rounds of separations; however, cell recovery will decrease.

How does the binding of the EasySep™ magnetic particle affect the cells? is the function of positively selected cells altered by the bound particles?

Hundreds of publications have used cells selected with EasySep™ positive selection kits for functional studies. Our in-house experiments also confirm that selected cells are not functionally altered by the EasySep™ magnetic particles.

If particle binding is a key concern, we offer two options for negative selection. The EasySep™ negative selection kits can isolate untouched cells with comparable purities, while RosetteSep™ can isolate untouched cells directly from whole blood without using particles or magnets.
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Data and Publications


CAMA cells were seeded into whole blood at a starting frequency of 0.98%. The CAMA cell (EpCAM+) content of the enriched fraction is 92.02% with a 3.8 log depletion of CD45+ cells

Figure 1. Typical EasySep™ Direct Human CTC Enrichment Profile

Starting with human whole blood from healthy donors, spiked with approximately 1% of CAMA cells (epithelial tumor cell line), the typical CTC (epithelial cell+) content of non-lysed final enriched fraction is 79 ± 16 % (using the silver “Big Easy” EasySep™ Magnet; gated on DRAQ5™ for nucleated cells). Typically the log depletion of targeted CD45+ cells is 2.8 to 3.2. In the above example, CAMA cells were seeded into whole blood at a starting frequency of 0.98%. The CAMA cell (epithelial cell+) content of the enriched fraction is 92.02% with a 3.8 log depletion of CD45+ cells.

Publications (1)

Scientific reports 2020 Label-free detection of rare circulating tumor cells by image analysis and machine learning. S. Wang et al.


Detection and characterization of rare circulating tumor cells (CTCs) in patients' blood is important for the diagnosis and monitoring of cancer. The traditional way of counting CTCs via fluorescent images requires a series of tedious experimental procedures and often impacts the viability of cells. Here we present a method for label-free detection of CTCs from patient blood samples, by taking advantage of data analysis of bright field microscopy images. The approach uses the convolutional neural network, a powerful image classification and machine learning algorithm to perform label-free classification of cells detected in microscopic images of patient blood samples containing white blood cells and CTCs. It requires minimal data pre-processing and has an easy experimental setup. Through our experiments, we show that our method can achieve high accuracy on the identification of rare CTCs without the need for advanced devices or expert users, thus providing a faster and simpler way for counting and identifying CTCs. With more data becoming available in the future, the machine learning model can be further improved and can serve as an accurate and easy-to-use tool for CTC analysis.
View All Publications

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