Patent ID: 6783992
Filing Date: 2004-08-31
Classification: B01L,G01N,Y10T

Abstract:
A method for selectively separating components having a molecular weight below a threshold value from a multi-component fluidic sample, said method comprising:introducing said multi-component fluidic sample into a micro-fluidic device having a fluid flow path and at least one micro-valve comprising a phase reversible gel material having a first porosity that can be modulated in response to an applied stimulus to provide a second porosity; and contacting said introduced multi-component fluidic sample with said micro-valve under conditions sufficient for said components of said multi-component fluidic sample having a molecular weight below said threshold value to at least move into said micro-valve while the remaining components of said multi-component fluidic sample having molecular weights above said threshold level are excluded from entering said micro-valve and thereby remain outside of said micro-valve; wherein said method comprises modulating the porosity of said micro-valve by applying said stimulus to said gel having said first porosity to provide said gel with said second porosity that selectively allows sample components that have a molecular weight below said threshold value to at least move into said micro-valve while excluding entry into said micro-valve of sample components having molecular weights above said threshold value.