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Frequently Asked Questions

Why do I need to provide an expiry date or a retest date for my sample?

We ask for an expiry or retest date to ensure that your test item is within its established shelf life specifications when stored under defined conditions – it’s all part of our work being performed in line with GLP (Good Laboratory Practice). It’s important that this is a true expiry date or retest date as it helps us make sure your test item is behaving as it should, and the results you get from us are correct.

Which skin irritation test do I need?

This depends on whether you need the test for EU regulatory purposes, in which case Skin Irritation OECD TG 439 might be right for you, providing a binary answer as to whether your item is an Irritant or Non Irritant, or for product development. Our non regulatory test uses the ET50 method and is used to place your item into a rank order of irritation potential or compare it against industry benchmarks. We’re more than happy to chat through the different test methods, or can introduce you to one of our regulatory consultancy partners who can help you make the decision.

Do you offer work placements or internships?

We don’t have an internship programme at the moment but do offer occasional work placements to university students who are interested in animal-free test methods. If you would like to apply, please send your CV and a covering email explaining what our values mean to you to info@x-cellr8.com.

Can we interview someone from XCellR8 for a project we are working on?

Please send any media or study requests to info@x-cellr8.com for the attention of our Marketing Director, Susie Lee-Kilgariff.

Where do you get your human cell cultures from?

We have long standing relationships with global biotechnology companies who we buy our tissue models from. They source them from consenting donors, usually as a by-product of cosmetic surgery.

What happens if I can’t provide a molecular weight for my test item?

This request only applies to the DPRA test. If you aren’t able to provide the molecular weight, you can detail the list of constituents with percentage compositions and we can approximate it using the guidance in the Test Guideline. As a last resort, the test item may be run neat (liquids) or dissolved at the highest soluble concentration (solids) then combined at a 1:10 or 1:50 ratio using the Cysteine and Lysine containing peptides respectively.