Hi all,

I am doing some work infusing different sized
particles through PDMS microchannels. These particles
range in size from 300 nm to 6 um diameter and are
made from polystyrene. I am having a bit of trouble
with particle attachment to the PDMS. It appears as if
the particles are attracted to the PDMS and can only
be dislodged using ultrasonic vibration but this is
also not always complete.

I have tried adding detergent (SDS) or inert protein
(BSA) to my fluid and this seems to help but does not
completely eliminate the problem.

Has anyone else seen this particle attachment problem
and have any suggestions on how to eliminate it.

Thanks,

JZ