Re: flow sorting magnetic beads

Hi

Most magnetic beads that are commercially available are paramagnetic, 
therefore will only be magnetic when in a magnetic field. Therefore the 
beads won't affect the flow cytometer with regards to magnetism.    As 
for the detection of the beads on the analyser it depends on which beads 
you use.  Dynal beads are 0.5um in size, and in my experience I have 
seen them on the machine esp as the beads seem to aggregate.   Whereas 
Miltenyi Beads are smaller only 50nm in size and therefore won't show up 
on a flow cytometer.  With magnetic beads it is often possible to do 
negative depletion therefore the cells you want won't have any beads 
attached to them and won't be activated in any way - important if you 
separating cells such as  monocytes.  Also Dynal have a kit to remove 
the beads from the cells  after separation.

Hope this helps

Rachael



Julia Sandberg wrote:
> Hello,
>
> I noticed that the last thread on flow sorting magnetic beads was from 
> year 2000, so I was just wondering if anyone has got any news 
> regarding this, since then? Do the beads accumulate in the FACS, or 
> damage it? And does the magnetism of the beads interfere with the 
> sorting procedure? We are using a FACS VAntage. 
>
> I would be greatful for all input!
>
> Best Regards,
>
>
>
> ________________________________________________
>
> *Julia Sandberg*
>
> M.Sc.Eng. Ph D student
> Department of Gene Technology
> Royal Institute of Technology (KTH)
> AlbaNova University Center
> 106 91 Stockholm, Sweden
>
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>

-- 


Dr Rachael Walker
Flow Cytometry Core Facility Manager
Wellcome Trust Centre for Stem Cell Research
University of Cambridge
Tennis Court Road
Cambridge
CB2 1QR

01223 760227