Surfactant like coating for glass (to stop PS beads binding)

[Matthew Davies]

I'm a microfluidics researcher trying to develop a bead based  
separation method. I have a problem with non-specific binding of  
biotinylated beads over a glass slide (forming the base of the  
channels) partially coated with streptavidin. Plain glass (slide  
cleaned with 1:1 MeOH/HCl for 30 minutes). I have tried the  
manufacturers suggestion of running the beads with blocker &  
surfactant to prevent binding and it worked fine. I have determined  
that its the surfactant that prevents the binding. Priming the channel  
with a surfactant solution doesn't help, but in the final application  
I cannot have surfactant in the solution. My hope is that there is a  
coating that I can apply, either by running a solution down the  
channel or by dip-coating the slide, that is compatible with  
streptavidin. I have to precoat the slide with streptavidin over a  
specific region, so any other coating has to come after.

I know this is sort of a weird question for this forum. So thanks in  
advance for all the help.

Dr Matt Davies
Microfluidics and Microengineering Group
STRI
University of Hertfordshire

PS resending this as it hasn't been posted yet and thought maybe it  
was because the first one wasn't in plain text format.