>>I would have thought the name would be changed - why market a new drug under the same name as an obselete drug?
Generally in China inexplicable product differences relate to cost; savings/substitution
>>This sounds odd. I'm not sure I understand what is meant by that - so they are saying it's Lufenuron in the bottle but with the certificate of analysis (CoA) for a different product?
Yes, that's what it seems, quote "about the structure, sample what we sent is lufenuron, in the test report, it should be impurity formula(not lufenuron)"
>>I take it they did not go for the professional approach and apologise for the mistake and send you the CoA for Lufenuron?
, In China if you can slide by without an apology you save face and complexity both at the same time. I don't like it but that's how it is.
>>I would be tempted to get in touch with a university chemistry department - most have mass spectrometry services, mass spec will give you an answer. That is probably the cheapest way to check.
Ok, I'll investigate that, and thanks for all the help, the explanations got me to understand what's real Lufenuron and what's not, I just have to see which one my sample is.
Oh, and they let slip (if true) that fudged, uncertified COA's are because no Chinese Lufenuron factory has passed a "GMP audit", (apparently commences EU 11Jul2013)
Excuse, can't figure out the quoting!