Tuesday, September 9, 2014

How to setup pSMART on the Q Exactive


ASMS was abuzz this year, with all sorts of new stuff, particularly on the DIA front -- wiSIMDIA on the Fusion really kinda took the front page, but if you were around the Thermo user's meetings you'll recall the mention of the new pSMART method for the Q Exactive HF.  pSMART is similar to the wiSIMDIA, where full scans and SWATH data are mixed together.

What I think got lost a little in the message was that pSMART works on EVERY Q Exactive, not just the QE HF.  The speed of the QE HF makes pSMART work a little better, but there is no reason you can't run this on every QE.

Want an simple easy powerpoint that shows you how to set it up?  Click here!

Wait.  Are you thinking "what was that one again?"

I probably should have started there I guess.

pSMART is a hybrid DIA method.  It is based on this thought "we need lots of MS1 measurements across the peak to do quan, but we can get away with just one MS/MS event to confirm the identity of the peptide we're looking at".

The idea is to time it out so that you get only 1-2 events MS/MS events for each peptide and you quan on the high resolution accurate mass MS1 ion.  The benefit is increased dynamic range over regular old SWATH (more sensitivity).  The trade off is that you have to quan at the MS1 level rather than the MS2 so you *may* lose some selectivity (if you are someone who believes that low resolution MS/MS fragments are more selective than high resolution MS1 peak IDs...I personally don't fall in that camp, but that's just me.  I look at this and think WIN!!!!

These slides are courtesy of Scott Peterman.

1 comment:

  1. the powerpoint link is broken, can you provide the document?
    thanks
    cagakan

    ReplyDelete