Automating Clinical Sample Prep – Immunosuppressants in Whole Blood

Martin Perkins

24th March 2011

Blood Cells

Red Blood Cells

The main goal of our LC-MS lab currently is to produce a suite of applications that will help clinical laboratories become more productive and more easily match the demands made upon them.

Having successfully completed the project to fully automate the analysis if vitamin D in blood serum, with the help of Leicester Royal Infirmary, we turned to another commonly performed analysis – the determination of selected immunosuppressent compounds in whole blood samples.

Our first task was to work out how to automate the sedimentation of the red blood cells in the samples and in the event, this turned out to be pretty simple and well within the capability of the CF 100 robotic centrifuge. From here we ended up developing two methods, one that used a solid phase clean-up of the serum and another, faster, sample preparation process that involved the injection of the serum directly. This second method, gave excellent results and although it may cause the LC-MS to require more maintainance in the long-term, it does enable the whole system to crank through samples at a rate of one every 5 minutes.

Once we had the method working in our lab we then performed a 200 sample comparison with Liverpool University Hospital and were rewarded by obtaining pretty much perfect correlation between the two data sets.

Paul Roberts, who carried out the work, has written an application note that shows this in some detail and a copy is available for download below.

If this is an application that you have any experience of or any interest in – we would welcome your feed-back.