Chromatography Forum

Hey, I have been suffering a ELSD signal unstable problems for a while. Here are the conditions we are using

Purity by HPLC
HPLC System: Agilent 1100/1200 HPLC System
Flow Rate: 0.5 mL/min
Mobile Phase A: 0.04% TFA in Acetonitrile
Mobile Phase B: 0.04% TFA in Water
Column Temperature: 50°C ± 5°C
Autosampler Temperature: Ambient
Run Time: 16 minutes

Detection System: Shimazu ELSD-LT II
Temperature: 75°C
Gas Pressure: 50 psi
Detector Environment: 50HƵ

However, the %RSD for system suitability is out of 10%. Could anyone have an idea about solving the problem. Appreciate it!

What are you analyzing? Make sure that your compound is not volatile, otherwise at lower concentrations you will lose linearity. Try to reduce temperature to 50 or even 35 degrees Celsius.

To follow up with what was said previously. I think the ELSD temperature is too high. Try nearer 30C to see if that works better.
Kevin