Naturally, we at Science.bio might have a bias in answering this question and would hope that any potential client would consider purchasing their reference materials from our store. That said, we understand it would be impossible to satisfy the needs of every researcher, so how do you choose a vendor?
The most important thing to keep in mind is to source from a reputable vendor that is able to provide independent third party lab test results and batch & lot tracking.
What kind of third party results should a vendor have?
At minimum they should verify the purity and identity of each batch of raw material and the concentration of every lot of finished goods. So if they sell a powder they should be able to provide identity and purity test results for each batch of that powder. If they sell solution with a concentration of 10mg/mL they should be able to provide identity and purity testing results and, additionally, concentration results showing the product has the correct concentration of 10mg/mL ±10%. Hence the importance of batch and lot tracking to ensure every batch and lot is tested.
What are some common red flags to look out for?
If a vendor does not provide batch and lot coding on their products. If they don’t have any test results. If they only have certificates of analysis and can’t provide actual chromatograms or spectrographs on request. If the “third party lab” has no contact information, you can’t get ahold of someone, search results are minimal and nobody has heard of this laboratory before. If they have only one lab report for a product they’ve been selling for years, suggesting they don’t routinely test their raw material or production runs. If they have lab reports for purity and identity but not concentration. If their testing is in house. There’s a lot of ways for vendors to get this wrong, there’s only one way to get it right, and it’s not worth taking a risk on a vendor who can’t get this right.