UPLC conversion

[chandusabini]

Dear Friends

I have developed a HPLC method of test concentration 0.01ppm with response 39000. I have tried to adopt the same method to UPLC to get better repsonse. But i have not succeeded in that more over i am getting the 18000 response only. What is reason behind this. I am looking forward for your advise.

Regards
Chand

[tom jupille]

I hate to nitpick, but there is no way to comment intelligently without a lot more information.

First of all, more detail would be helpful: what size column, flow rate, injection volume did you start with, and what are you using with the UPLC system?

Second what do you mean by "response" (area? peak height? what units?)?

Third, what really matters as far as sensitivity is concerned is signal/noise ratio. How does that compare between the two systems?