Purity and Price Are Not Correlated!
The prices charged by biomedical reagent vendors for a given product tell you
nothing about the purity.
For example, as shown in our Purity/Price Comparison Table for Rapamycin you
- $182 to Abcam for 1 mg of 98% pure rapamycin
- $245 to R&D Systems for 1 mg of 98% pure rapamycin
- $252 to Sigma for 1 mg of 95% pure rapamycin
- $438 to Calbiochem (EMD) for 10 mg of 99% pure rapamycin
- $53 to LC Labs for 50 mg of >99% pure rapamycin!
Another example is cyclopamine:
- Among the many other cyclopamine suppliers, 19 suppliers charge $18 to $194 for 1 mg;
only 3 suppliers claim >99% purity; 12 claim only 98%; and another 4 claim only 97%.
- LC Labs' price for 25 mg of >99% pure cyclopamine is $84—$3.36 per mg—1/5 to 1/64 of the cost from the suppliers noted above.
The picture is clear -- price tells you nothing about quality.