Resources

Browse our articles

Safety Testing

Browse all articles

Animal-free Testing

Browse all articles

Efficacy Testing

Browse all articles

Regulation and Compliance

Browse all articles

XCellR8 News

Browse all articles

Frequently Asked Questions

What do you need from me to start a test?

Firstly, we ask you to approve our quote and send us a PO number. We’ll then ask you to fill in an information sheet about your product or ingredient which includes some information such as the lot number, expiry date, purity and storage conditions required. We’ll ask for a description of the item (its name, colour and physical state) which will need to match the sample you supply. For some tests, we’ll also ask you to supply the molecular weight. If you have a Material Safety Data Sheet (MSDS), please also send us that. And last but definitely not least, we’ll need a sample of the item(s) you want to test sent to our laboratory in Cheshire, UK. 10ml if it’s a liquid or 10g if it’s a solid.

We don’t use a Purchase Order system or else Purchase Orders take a long time to issue in my organisation. Can I still start my study?

Yes. In these circumstances, we will usually issue the invoice at the beginning of the study and ask for payment within 30 days.

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.

What test do I need for my material?

The place to start is to establish if you need the test results as part of a regulatory submission, or whether you want to discover a substance’s properties as part of a product development or pre-clinical programme. We’re always happy to advise before you start so please feel free to call if you’re unsure.

How long will my test take?

XCellR8’s tests can take as little as 4 weeks, up to a maximum of 12 weeks. We’ll always try our best to accommodate urgent requests. Please do bear in mind that the timeframe starts at the point we receive your sample and the accompanying information that we ask for in order to start a study, and finishes when we send your draft report.

Which skin sensitisation test do I need?

Current regulatory guidance for in vitro skin sensitisation testing is to adopt the “2 out of 3” approach, whereby 2 positive results out of the 3 tests (OECD TGs 442c, 442d and 442e) results in classification as a Skin Sensitiser. If you perform two of the tests and get matching results, this strategy states you can have confidence in the result without the third test. If they have different results, proceed to the third method to find a definitive result. Each of the three methods has different requirements regarding the solubility of your test item, so contact us to find out which will be best for you. You can also read more about the test methods here.