Chromatography Forum

Dear Friends,

I am using Waters HPLC-Fluorscence with Kobra cell (Rhone diagnostic) for Aflatoxin analysis. And we always face the problem of flow cell leaking and every year we end up with re-building the flow cell or repalcing with new flow cell.

The engineer saying that this is due to the high pressure exerted by Kobra cell. We are using the peak tubes suggested for use, but even we are facing this problem repeatedly.

Can anyone facing similar problem and suggest me to rectify the recurrence of this problem.

Thanks in anticipation,
Anish

Hi Anish,

Please remove the column and insert a connector in the flow path. Then set the flow as stated in your protocol (1 mL/min?) and read the pressure after awhile. Let us know what the presser reading was.
Also, check the detector/flow cell specifications with regard to pressure limit.
Maybe you’ll need to utilize a larger diameter capillary from the detector outlet to the waste reservoir.

Best Regards

... and also,

Let us know what tubing (type, length, internal diameter) is connected after the detector cell.

Sir,

Thanks for your valuable reply.
We have connected Detector out to Kobra - The length of peak tube is 53.5cm(approx);I.D-0.02"(inches).

And Kobra cell out to waste - length of peak tube is -34cm(approx);I.D-0.02"(inches).

detector/flow cell specifications with regard to pressure limit is 16microlitre flow cell, Max. pressure 1000kpa(145psi).

Can you pls look into this and reply.

Thanks
anish

The pressure limit on your cell is low. You should connect larger diameter tubing after the detector, and the tubing should be as short as possible.