Re: Sorting of defined amounts of events

Ultan,

I'm guessing you are sorting using your MoFlo.	If so, the count of  
sorted cells is corrected for the aborted sort events so that  
Christopher Bare's suggestion of sorting slowly is probably  
unnecessary.  The other question is whether you are sorting "purify  
1-2" or "single".  If the former, you may get more than 1 cell for  
some sort events and I don't know for sure if the MoFlo corrects for  
this in the count.  However, having said all that, I think your main  
problem is not inaccuracy in the numbers of cells you put into the  
tube but rather the difficulty of getting them out again intact and  
viable.  My clients routinely use the traditional haemocytometer  
count.	An alternative would be the bead method: Add exactly 100,000  
beads to your purported 1,000,000 cells in the tube and an analysis  
of an aliquot should show 10.0 cells per bead if the cells are all  
still there.

Frank Battye
[With appropriate restraint, completely avoiding any rhyme or metre  
characteristic of any verse form from your home county or elsewhere]

On 06/12/2007, at 8:19 PM, Ultan Cronin wrote:

> I've a couple of simple questions for those with sorting know-how:
>
> What factors affect the sorting of defined large amounts  
> (1,000,000) of events into a tube?  What are the standard ways of  
> proving that I have exactly 1,000,000 of the suckers in the tube at  
> the end of the sort?
>
> No limericks from down under this time please!!!

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