PTFE frit in Quat Pump always dirty

Hello! I have slightly increased the amount of use my HPLC gets but I am having to change the PTFE frit in the Quat pump what seems like a lot more often. Probably once to twice a month. Is there anything else that anyone thinks that could be causing it to get dirty? Or is it more likely to just be from just the increased usage? We do not have a normal maintenance routine as we are a very small company. I am working on developing one.  Thank you for any help you can provide!


ETA: I am having pressure issues when this happens and causes it to stop working. I forgot to mention this.

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  • Good solvent quality is vital, so try a different supplier or a better grade. As I said earlier, membran filtration of all solvents is a good idea. Make sure a PM gets done, if the system hasn´t seen one in the last twelve months.

  • So we had this problem when we first starting using the 1260 systems. We would add a standard column (100 x 3.0mm), and after less than 100 injections of solvent based material it would give us huge backpressures and stop the injections. We blamed the column manufacturer at first, so switched to another column from Agilent, and it still happened. We changed various tubing, heat exchangers, and frits for the solvent lines, all with only short-term success. 


    We eventually traced it back to needing to filter our mobile phase solutions. We now filter absolutely everything attached to a HPLC line using 0.2um nylon filters. We also added a pre-column filter (0.2 or 0.5um) and a guard column and now we have no pressure issues. We change the filters when we see poor peak shape, or increasing pressures (we follow the pressure profile for each batch). We also try to flush out the HPLC system every 6 months, there's a HPLC flushing solvent available from Agilent which we use, and I can send you on the protocol we use if you want.


    So, filter everything, and clean your HPLC before you try doing more injections, otherwise we only got temporary relief of the pressure buildup. Our systems were brand new when we experienced these issues. 


    Hope this helps!



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