1. Will Dead-Cert^® Nanoparticles work on my cells?

Almost certainly, yes. Dead-Cert^® Nanoparticles are designed to work on all cell lineages from worms to mammals. ImmunoSolv and its customers have successfully used the technology in multiple cell types from a variety of species.

2. How many cells can I separate and how many Dead-Cert^® Nanoparticles do I need?

The technology can be scaled up or down to suit users’ needs. Typically, 20 ml of stock suspension of Dead-Cert^® Nanoparticles is sufficient to separate around 5 million cells. This means that one kit is sufficient for around 150 million cells.

3. Can I use my cells’ preferred culture medium to carry out separations?

Dead-Cert^® Nanoparticles work in many types of culture medium. The key to efficient separation is having a mono-dispersed suspension of cells. ImmunoSolv’s Dead-Cert^® YES medium (provided with the kit) helps to optimise the system for maximal yields of viable cells.

4. When exactly after thawing should I separate cells to improve their growth and productivity after they have been stored in liquid nitrogen?

Cells often appear highly viable immediately after revival but during the first few hours in culture substantial numbers can die as a result of stress responses caused by the temperature changes of freezing and thawing. We recommend separating viable cells after overnight culture following revival.

5. Will Dead-Cert^® Nanoparticles work on primary cells?

Yes, Dead-Cert^® Nanoparticles are designed to work with both cultured cell lines and primary cell suspensions.

6. I appreciate the application of Dead-Cert^® Nanoparticles to suspension cultures. My cells are adherent and so I can simply wash away non-viable cells. What are the advantages of Dead-Cert^® Nanoparticles to me?

The myth that non-viable cells can simply be washed away stems from the lack, until now, of good technology for efficient and simple dead-cell removal. Washing adherent cells can (a) leave dead cells behind (they often remain adherent to the substrate) and (b) results in loss of viable cells. Use of Dead-Cert^® Nanoparticles on adherent cell lines at the point of passage when the cells are in suspension is the most efficient mode of selective removal of non-viable cells from adherent (as well as suspension) cultures and improves growth of adherent and suspension cells alike (see, for example, ImmunoSolv “Stem Cells” datasheet).

7. My cells grow in aggregates. Can I use Dead-Cert^® Nanoparticles to isolate viable cells from these cultures?

Yes, use Dead-Cert^® Nanoparticles after dispersing the cells into single-cell suspension. Suspensions of single cells are critical for optimal efficiency of the technology.

8. Can Dead-Cert^® Nanoparticles be used to remove non-viable bacterial cells?

No. The technology is designed to detect membrane changes that occur on cells of eukaryotes.

9. Will Dead-Cert^® Nanoparticles alter the state of activation of my cells?

The particles are inert and the negative selection process leaves viable cells untouched. There is no evidence that the selection process alters the phenotype of any cell type.

10. At what temperature can I use Dead-Cert^® Nanoparticles?

The selection of viable cells using Dead-Cert^® Nanoparticles can be carried out efficiently at any temperature between 2°C and 37°C. At physiological temperature, certain cells that have natural phagocytic or endocytic capacity could take up particles in the viable state and therefore can be removed along with non-viable cells. In such cases, separation at lower temperatures is recommended.

11. Is there anything about the surface property of the nanoparticle coating that will prevent their entry into healthy cells?

No, technically they could be phagocytosed (this would need physiological temperature) but following the optimisation of separation it is possible to recover 100% of viable cells which argues against uptake by healthy cells. Phagocytic cells like macrophages should be separated at room temp or in the fridge but other cells can be treated at 37C.

12. Are Dead-Cert^® Nanoparticles environmentally friendly?

Yes, the kit packaging is made of entirely card-board. There is minimal plastic waste disposal (no columns), no toxic reagents and the used nanoparticles can be safely discarded into drain.