there wont be any change in RT.

when you are running two polarities at same time for the analytes having same RT only thing you need to take care of is dwell time .

there wont be any change in RT.

when you are running two polarities at same time for the analytes having same RT only thing you need to take care of is dwell time .

the quantification is possible for compounds that have the same retention time.

Yes, there is no problem with them being able to switch polarities and quantify one compound in negative mode and one in positive mode.  The one thing to watch out for is the switching time, which will be a lot longer than the minimum dwell time.  You will need to ensure that you can get enough point across your peak for each analyte, and the polarity switching time for the Quattro Micro is 100 milliseconds, and then you need to add the dwell time to that.  I can't remember exactly, but I think the minimum dwell time for the Quattro Micro was around 10 millisecond. 

So if you need 15 points across the peak and have 2 peaks at the same RT, that is 15 points * 2 peaks * 0.110 seconds per scan = 3.3 seconds is the minimum width for each peak.  That should be pretty easy to achieve.

The other parameters should be the same.

Here is a reference that discusses that exact scenario, also attached:

http://www.waters.com/webassets/cms/library/docs/720001418en.pdf

Thank Chris! Exactly what I'm needing!!!

I don't know why the site changed my questions. They became so ridiculous! =)

Here comes the original:

"Has someone worked with Waters Quattro Micro, in both polarities, and knows if the equipment can quantificate 2 compounds, one in negative mode and one in positive mode but at the same retention time? What were the parameters? Dwell?"