sample preparation and column cleaning

[Dedi]

Dear All members,

This is my first post to this forum, thx to mr syx for introducing me this forum, do you still remember me? I guess you are Mr. Siswanto from Interbat?

We're developing a method of analysis by HPLC from OBH syrup formulation. We didn't do clean up sample preparation, we just dilute the sample by mobile phase, filter by miliphore 0.45 micron, then inject to the system. The method is satisfy for certain time of analysis by new column package, but the column is quicker blocked and become high back pressure than others method. we use Lichrospher 100 RP-8, 5 micron.
is it OK for the sample preparation, due to the sample matrix is viscous?
why the column is quicker blocked than others method with the same mobile phase and column cleaning procedure?

Any suggestion for effective column cleaning program?

Thank you

[bartjoosen]

Lichrospher has already some higher backpressura like some other columns with the same dimensions.

You could use a guard column (available for the lichrosper cartridges), or you could reverse you column and use a cleaning procedure, which is easily found on the back of the COA of the Lichrospher column (regenerate with: water-methanol-chloroform-methanol-water in this sequence)