Frequently Asked Questions

Where can I find protocols and/or scientific literature regarding testings with the skin models?
Please have a look at our Information Center. Here you can find protocols, video tutorials and references.

What are the quality parameters for tissue model batch release?
All tissues are qualified according to tissue architecture and tissue viability.

How long can I use the tissue models for my experiments?
The recommended time period for conducting experiments with the standard FT skin models is 10 days, for the FT LONG-LIFE model 50 days after arrival at your lab. The epiCS models should be used within 7 days.

Which different kinds of epiCS models do you offer?
We offer epiCS models w/o melanocytes and epiCS models with three different pigment levels: Caucasian, Asian-Caucasian and Afro-American donors.

What are the dimensions of your skin models?

What is the origin of the skin cells ‏(neonatal or adult)?
Human keratinocytes and fibroblasts, used to construct our skin models, are isolated from neonatal foreskin.

Are fibroblasts and keratinocytes in the FT skin models derived from the same or from different donors?
The skin models are produced from cells of single donors.

How far in advance should I order the tissues?
It is recommended to order the tissues at least 5 weeks in advance to guarantee you the requested number of skin models. Spontaneous requests are possible but depend on existing capacities.
Exception: For FT LONG-LIFE models, please contact us (info@phenion.com).

What are the prices for the tissue models?
Please find the prices for our models, media and accessories in our price list.

What is included in the price?
The prices for our skin models are costs per single tissue. Culture vessels and special accessories, needed to take the tissues back into culture, are included in respective amount.

How can I order skin tissue models, medium or accessories?
Please use the Request for Quotation form or send us an E-Mail at info@phenion.com.

What is the minimum order quantity?
Minimum order quantity is 6 units in general. For less tissues, please contact us at info@phenion.com.

How do I pay my orders?
Invoicing is processed on basis of served orders. In general, at the end of each month the invoice is released and sent by standard mail or as digital version (PDF). Payments will be conducted by wired bank transfer with given bank details displayed on the invoice.

How long does the shipment of the models take?
We are striving to ship the models within 24 hours in Europe. However, due to the massively increased volume of cargo in the wake of the COVID pandemic, shipment within this time cannot be guaranteed from the transport companies. In general, all destinations that can be reached within 72 hours are eligible as delivery areas.

How do you transport the tissue models?
The models are shipped in specially designed transport boxes on top of a transport gel to maintain tissue vitality and physiology.

On which day of the week are the skin models shipped?
In general, epiCS and FT skin models are shipped on Monday but can also be delivered upon request in the week before at earlier differentiation states.

How do I take care for the skin models after arrival in my lab?
Please, follow the Instructions of Use and the respective video in the Information Center.

Which medium should be used for the culture of the FT skin models?
Please use the Phenion® Air-Liquid Interface Culture Medium. It is also available in special variations (i.e. w/o antibiotics, hydrocortisone, or phenol red).

Which medium should be used for the culture of the epiCS models?
Please use the epiCS® Culture Medium. For epiCS-M models epiCS-M Culture Medium is recommended. If needed, it can be ordered in special variations (i.e. w/o antibiotics).

How long should the tissues be equilibrated after arrival before starting the experiment?
The models should be equilibrated for at least 2h or better overnight in fresh culture medium before using them for testing.

How do I take the FT INSERT skin models out of the cell culture insert?
You can easily remove the FT INSERT skin model from the insert with sterile rounded forceps.

How can I prepare histological sections of the tissue models?
Based on your equipment and application you can prepare frozen and paraffin sections.

Do you offer in vitro services?
If you are interested in in vitro test services, please contact us at info@phenion.com.

Which applications can be run with the epiCS models?
The epiCS models are validated for the in vitro skin corrosion (OECD TG 431) and skin irritation test (OECD TG 439). They are also suited for many other applications like the epiCS skin sensitization and potency test, the skin irritation test for medical devices, the phototoxicity test and the micronucleus assay.

Which applications can be run with the different FT skin models?
FT skin models can be used for many different applications, i.e. for genotoxicity assessment (3D skin comet assay), wound healing studies, TEWL measurement, collagen and elastin synthesis, transdermal drug delivery, skin barrier tests, microbiology etc.

Is the skin irritation test using epiCS models regulatory accepted?
Yes. It is part of the OECD Test Guideline 439.

Is the skin corrosion test using epiCS models regulatory accepted?
Yes. It is part of the OECD Test Guideline 431.

How can we validate the in vitro skin irritation and/or corrosion test in our lab?
We are offering epiCS validation kits for both endpoints to run a validation study in parallel at your and in our lab. Successful validation is certified respectively. Please contact us at info@phenion.com.

For which application do I need the nylon meshes and filter discs?
Nylon meshes are used for homogenous distribution of liquid test substances on the skin model surface in the epiCS skin irritation test and the epiCS corrosion test. Filter Discs are needed for epiCS® skin sensitization and potency test.

Is it possible to add bacteria or other microorganisms onto the FT skin models?
For any microbiological study we recommend working with our INSERT FT skin model. It is identical with the “standard” FT skin model but grown in a co-culture insert. This special feature allows the topical application of bacteria suspensions without risking that the microbes might escape into the underlying cell culture medium and consequently jeopardize your test.

Is it possible to inject substances or microorganisms into the skin?
Yes, it is possible to inject substances into the FT skin equivalent. Due to its mechanical robustness, it does not break during the manipulation (Stellavato et al., 2016).

Do you provide any skin model suitable for wound healing?
Wound healing studies can be conducted with the FT skin models.
Different wounding mechanisms can be applied:
- partial epidermal removal
- cutting
- thermal tissue damage.

The progress of wound healing can be monitored non-invasively with optical coherence tomography ‏(OCT), or on the basis of histological sections.

Is the skin model suitable for the study of transdermal drug delivery by patches?
Yes. A patch can be applied onto the near-dry tissue surface, and drug distribution and permeation, respectively, can be analyzed with HPLC, MS etc.

We would like to run the skin sensitization and potency test ‏(SSPT) in our lab for the first time. What are your recommendations?
We offer a SSPT training kit including epiCS models, culture medium, assay medium, MTT reagent, 6-, 24- and 96-well plates, solvents and controls which helps you to easily run the skin sensitization and potency test in your lab. For price information please contact us at info@phenion.com.

Where do I get support for establishing the 3D skin comet assay in my lab?
Please, contact us at info@phenion.com. We support you with our expertise to implement the 3D skin comet assay in your lab.

How do I apply a test substance on top of the tissue?
Liquids can be applied with a pipette, solids with a sharp spoon or spatula. Viscous material can be applied either with a paintbrush or a displacement pipette.

Is it possible to separate epidermis from dermis for severally compartment analysis?
Yes. Incubation of the FT skin model with thermolysin allows the separation of epidermis from dermis with the help of forceps.