NSAIDs by HPLC-DAD
Posted: Tue Apr 24, 2012 1:01 pm
Hello.
I am currently developing a method for Ibuprofen, acetaminophen, Naproxen, and Salicylic acid. Currently, I am using a gradient method using a combination of 0.1% Formic Acid in H20 and 0.1% Formic Acid in ACN. We are using a LLE. I am having issues with my internal standard. We have tried Benzoic acid as well as Mefenamic Acid. The area will remain stable for the first four concentration points but they for some reason will double for the last two. Any suggestions will be greatly appreciated.
I am currently developing a method for Ibuprofen, acetaminophen, Naproxen, and Salicylic acid. Currently, I am using a gradient method using a combination of 0.1% Formic Acid in H20 and 0.1% Formic Acid in ACN. We are using a LLE. I am having issues with my internal standard. We have tried Benzoic acid as well as Mefenamic Acid. The area will remain stable for the first four concentration points but they for some reason will double for the last two. Any suggestions will be greatly appreciated.