Chromatography Forum

Hello everyone,
I'm quite new to analytical chemistry, so I've maybe got a noob question for you:

I have do develop a method to measure polyamines in wheat samples by HPLC with UV detection (254 nm), pre-column derivatization with dansylchloride. I can already measure and quantify desired polyamines (less than compared with HPLC-MS, but that's another question...). Most protocols recommend filtration with 0.45µm filters, and a very few centrifugation, some both.

So, my simple question is:
Can i centrifuge my samples (10000g or more, 5 minutes) prior injecting into my HPLC system, instead of filter them with 0.45 filters? Or could this eventually harm my column, or even lose some of my analytes, other disadvantages? It would be much easier, less time and money consuming to simply centrifuge them.

Centrifuge would settle out most particulates, but you would need to be extremely careful not to shake the sample and allow them to become resuspended. I would centrifuge to remove the bulk of the particulates then filter to be certain there was nothing to clog the column. You can purchase quite a few filters for the price of a column.

It really depends on the sample and how careful you are. Sometimes I recommend people that wish to avoid filtering that they centrifuge twice and transfer to a new tube in between. In any case you should always control that samples are free of particles just before injecting into your HPLC since precipitation might occur even after filtration, for example during storage at -20 or -80°C.