Frequently Asked Questions

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cellQART® Pro TIps FAQ

What else should we monitor in addition to routine cell counts?

Almost all cells do best in a tight range of incubation parameters (temperature, CO2 concentration, media condition, humidity, amount of light, etc.). Keep deviation to a minimum.

We are performing tumor invasion studies. Are there any extra considerations?

Many in the field put a Matrigel or other firm coating on the membrane to better observe cell invasion to the other (bottom) side.

Does transparency influence our cell migration analysis?

The higher porosity of translucent membranes allows for easier cell migration and, consequently, more observations.

We are performing cell migration/invasion studies; is pore size important?

Yes, it seems that 3 µm – 8 µm pore sizes are best suited for these studies; but it is critical to check cell size first.

We’re not sure our seeding cell density is optimal. What do we do?

Experiment with two (2) or more densities lower and higher than the current value. Proceed in the direction of improved results.

We want cell growth on both sides of the membrane. Is this possible?

Yes! When mounting on both sides of the inserts, first mount cells on the bottom side.

Some in the field still use insert/membrane coatings even though cellQART® inserts are tissue-culture treated. Is this necessary?

While our membranes are tissue-culture treated to stimulate adherence, some cell types benefit from additional coatings that facilitate growth.

We’d like better initial cell attachment, is there something we can do?

Prior to seeding, incubate the inserts with the intended media for at least 1 hour at the desired temperature

We need a certain level of transparency. Will that influence insert porosity?

Transparency increases as porosity decreases, so porosity requirements will impact transparency.

We use fluorescence microscopy. Should we use transparent or translucent inserts?

Both transparent and translucent cell culture inserts are suitable for fluorescence microscopy and fluorescent imaging applications. Each membrane type allows sufficient light transmission for fluorescent analysis, making them compatible with common fluorescence microscopes.

Transparent membranes are ideal when maximum optical clarity is desired, such as for high-resolution imaging, cell visualization, or detailed morphology studies.

Translucent membranes are also fully compatible with fluorescence microscopy and are frequently used in routine fluorescent assays, permeability studies, and transport experiments.

Ultimately, the choice between transparent or translucent inserts depends on your imaging resolution requirements, experimental design, and personal preference, rather than limitations in fluorescence compatibility.

Does the transparency of the membrane affect my results?

Yes. Membrane transparency can directly influence imaging quality and experimental monitoring in cell culture applications. Sterlitech’s transparent cellQART® track-etched membranes are optimized for phase contrast microscopy, live-cell imaging, and real-time monitoring of cell morphology and confluence. Improved optical clarity enables clearer visualization of cells without membrane interference, supporting more accurate assessment during transwell assays, co-culture systems, and permeability studies.

I am currently using polycarbonate membrane inserts and want to switch to cellQART®, how will that affect my cells?

cellQART® cell culture inserts feature a polyester (polyethylene terephthalate, PET) track-etched membrane rather than a polycarbonate membrane. Differences in membrane chemistry, surface energy, and pore architecture can impact cell attachment, proliferation, morphology, and differentiation. When transitioning from polycarbonate to PET membranes, variations in extracellular matrix adsorption and cell–substrate interactions may alter growth behavior.

To ensure optimal performance in cell culture, transwell assays, and in vitro permeability or migration studies, Sterlitech recommends performing seeding density optimization by testing both increased and decreased cell concentrations relative to your current protocol. This approach allows users to identify conditions that support improved confluence, barrier integrity, and reproducibility when using Sterlitech cellQART® membrane inserts.