PLURISELECT

NOTICE

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What are so-called targets or isolation targets?Targets are cells, proteins or microorganism from whole blood, buffy-coats, cell culture, primary cell isolation or cord blood samples. All targets can be distinguished and isolated by means of specific surface molecules (proteins, carbohydrate chains, ect.). pluriSelect’s proprietary isolation beads are surface coated with a target-specific antibody that will bind to the target and separate the target from unspecific cells or proteins. Bound targets are subsequently isolated through pluriSelect’s proprietary technology. Your targets are now ready for the use in cell culture assays, nucleic acid isolation assays or protein analysis assays.
How does the pluriSelect isolation technology work and why is it simpler compared with currently available systems?We direct our attention during the development process on the usability of our products. Our products are very easy to use and produce high-quality and reproducible results. The pluriBead platform is based on isolation of targets employing spherical, isodiametrical (monodisperse) beads with antibody coated surfaces. Targets bound to the surface of the beads are separated using a sieve or sieving cascade by which the targets are separated fromthe sample material(e.g. whole blood, buffy coats )
What is the difference to magnetic separation technologies?The separations beads developed by pluriSelect are not magnetic! The isolation technology is based on the separation of isodiametrical beads through the use of a proprietary sieving technology. That allows the application directly in whole blood without Ficoll gradient or similar prepartion steps.
How long does it take to isolate targets using the pluriSelect technology?
Thirty minutes! pluriSelect’s separation technology works faster than other available systems. For example, the separation of CD3(+ve) cells from whole blood is completed in 30 minutes. The reduced separation time is mainly achieved because common sample preparation steps such as Ficoll™ gradient density centrifugation are not necessary. Only three simple steps are to be performed until the isolation is completed:

(1) mixing of sample and isolation beads
(2) incubation at room temperature
(3) separation of targets using the pluriSelect sieves
and subsequent rinsing of the targets with buffer or medium.
At this step your cells are separated and ready for RNA/protein isolation (e.g. microarray , qPCR) ! If bead removal is necessary two very short steps are to be added to the above procedure:

(4) incubation of targets (here specifically cells) with removal buffer to detach the cells from the beads
(5) washing off the cells into tissue culture flasks or lysing the cells for RNA / protein analysis assays.

The total isolation time including the cell removal steps is still less than 50 minutes.
Sample preparation: Is it possible to separate cells or proteins directly from a whole blood sample? Are density gradient centrifugation steps dispensable?The pluriBead technology is especially developed to isolate cells or proteins directly from whole blood or buffy coats. Isolation beads are mixed directly with the blood sample and incubated in the provided mixing container (2ml , 15ml or 50ml).
The main determinant for the target specificity is the antibody bound to the surface of the separation bead. Other molecules in the heterogeneous sample do not interfere with the binding reaction. So, the removal of erythrocytes by density gradient centrifugation or erythrolysis prior to using the pluriBead cell isolation kit is not necessary. In fact, the viscosity of whole blood reduces cell stress and consequently minimizes the apoptosis rate of the isolated cells.
Temperature: Is it possible to isolate targets at room temparature? Why don’t I have to cool down the sample to 4° Celsius?Yes, the isolation of your cells / proteins / targets can be done at room temparature or 37° Celsius. Using pluriSelects isolation technique for targets from whole blood you will need no longer than 30 minutes to obtain your targets. Additionally, the physiological and rheological characteristics of whole blood reduce unnecessary cell stress that the isolation beads may have on the cells.
Sample volume: What is the appropriate sample volume for this separation method?Currently, we offer separation kits for sample volumes from 200 µl to 45 ml. Isolation kits for sample volumes of up to 50 ml will follow soon.
Is it possible to simultaneously isolate more than one target from my sample?Yes, absolutely! This is what is special about pluriSelect’s isolation technology. Currently, two different targets (cells and/or proteins) can be isolated from one sample in one single step. The target specific separation beads are mixed with 300 µl to 15 ml of sample volume in the mixing container and incubated at room temperature for 15-30 minutes. During incubation, the targets bind to their corresponding antibodies. As the beads for each target differ in their distinct size, the mixture can be separated by a sieving cascade with a bead-specific mesh size. After washing, the targets are isolated for further use. For more details please see our Technology page.
Is it possible to isolate nucleic acids from the isolated cells?With pluriBead it is particularly easy to educe nucleic acids from RNA/DNA separated cells. Following the isolation, cells can be lysed directly on the sieve using commercially available lysis buffer according to the manufacturers’ instructions.
What is the recovery rate for cell isolation?In contrast to other available systems, pluriSelect’s target isolation technology can do without unnecessary pipetting steps. This does not only reduce the loss of precious cells or proteins but also lowers the apoptosis rate. According to the kits’ design, an average 80% of the targets are retained and isolated.
Is it possible to cultivate the isolated cells still attached to the beads?Yes! Particularly cell lines used in cell culture experiments often have the ability to grow on different kinds of plastic surfaces without showing adverse effects. Cells attached to the beads can be transferred to your tissue culture dishes and the cells will attach to the plastic surface over time, depending on their mobility characteristics. If desired, during the next passage the beads can be removed using pluriSelects’ sterile separation sieve.
Cell stress: how much lower is the apoptosis rate and why is it so much lower compared to systems currently available?The cell stress is mainly reduced because of two inherent characteristics of the isolation kit: natural environment and minimal handling time. The target cells remain in their natural environment such as whole blood or cell culture solutions. Additionally, the number of steps or processes such as pipetting, cooling, centrifugation or changes to the cells' environment (Ficoll™ density centrifugation!) are obsolete or reduced to a minimum. This results in minimal mechanical sheer stress and the isolation duration is kept to a minimum. The isolated cells can recover in cell culture medium shortly after the isolation or can be used in other assays.
What equipment do I need to perform the separation in my lab?plurBead isolation technology requires only minimalist lab equipment. As sample preparation is not required, centrifugation steps are unnecessary. So, all you need is sterile pipettes and a fixed angle or tilting horizontal roller mixer (8- 15 rpm).
What is the optimal rotating speed for the horizontal roller mixer and why?The rounds per minute (rpm) setting of the horizontal roller mixer can be used quite variable. However, approximatly 10 rpm is optimal for a complete mixing of the sample with the separation beads. To guarantee a thorough and complete mixing of the sample and the beads, the rotation of the mixer should not fall below 5 rpm. At rotation speeds greatly exceeding the optimal settings, flow rates increase and the bead-target binding reaction may be reduced and the stress on your target cells increased.
Is it possible to remove the beads from the target cells?Yes! We have developed a physiological cell release process which allows the gentle removal of the catcher particles within 10 minutes at room temperature. In this case, the cells are separated from the catcher particles and a single cell suspension is obtained for downstream experiments such as FACS, cell culture experiments or nucleic acid isolation. All necessary reagents are included in the kit.
Cell depletion: how efficient does the system work if negativ selection of my sample is required?At present, the cell isolation technology pluriBead is the only system capable of depleting whole blood from specific cell types (= negative selection). In other words: the targets are removed from the sample and the eluate contains no or very little ‘target’ cells. On average 95% of targets can be depleted from the sample.
What purity do the isolted cells show?The average purity of isolated cells achieved with the pluriSelect technology is 95%.
Which isolation beads are currently available?As we are constantly increasing our product portfolio, please see our current product list for more information.
Are the materials supplied by pluriSelect sterile?Yes! All components of the kit, including beads, funnel, sieves and connecting ring, are sterile and separately packed. Each target isolation assay can thus be performed using routine laboratory cell culture techniques and equipment.
Is it possible to buy the individual components of the kit?Of course, all components contained in the kit can be bought from pluriSelect.
How can I order the pluriSelect target isolation kits?Kits and single components can be ordered at our products page.
Can I combine pluriBead with other magnetic separation systems?Yes, because pluriBead is a non magnetic isolation method you can use any magentic system for isolation or depletion after pluriBead to enrich or deplete a sub-population ( e.g. CD14 (monocytes) from CD4 (T-cells) isolation or Cd25+ Treg cells from CD4 T-cell isolation).