Microfluidic method for nucleic acid purification and processing

An integrated microfluidic device comprising microchannels formed in a generally planar substrate, said device comprising:

• an enrichment microchannel comprising an enrichment channel portion containing an enrichment medium, said enrichment channel portion having a first inlet and a first fluid outlet;
• a main electrophoretic microchannel enclosing a main electrophoretic flowpath, said main electrophoretic microchannel being connected in fluid-conducting relation to said first fluid outlet, and said main electrophoretic microchannel comprising a detection region;
• means for moving a sample into said enrichment channel portion by way of said first inlet and out from said enrichment channel portion by way of said first fluid outlet, whereby at least a fraction of a component of interest in the sample is retained by said enrichment medium,
• a discharge channel connected in fluid communication with said first fluid outlet at a point upstream from said main electrophoretic flowpath, for discharging a portion of said sample other than said fraction away from said main electrophoretic flowpath;
• and
• means for moving at least a portion of the fraction out from said enrichment channel portion by way of said first fluid outlet and into said main electrophoretic microchannel.

An integrated microfluidic device comprising microchannels formed in a generally planar substrate, said device comprising:

• an enrichment microchannel comprising an enrichment channel portion containing an enrichment medium, said enrichment channel portion having a first inlet and a first fluid outlet;
• a main electrophoretic microchannel enclosing a main electrophoretic flowpath, said main electrophoretic microchannel being connected in fluid-conducting relation to said first fluid outlet, and said main electrophoretic microchannel comprising a detection region;
• means for moving a sample into said enrichment channel portion by way of said first inlet and out from said enrichment channel portion by way of said first fluid outlet, whereby at least a fraction of a component of interest in the sample is retained by said enrichment medium;
• a discharge channel connected in fluid communication with said first fluid outlet at a point upstream from said main electrophoretic flowpath, for discharging a portion of said sample other than said fraction away from said main electrophoretic flowpath;
• means for moving at least a portion of the fraction out from said enrichment channel portion by way of said first fluid outlet and into said main electrophoretic microchannel;
• and
• a plurality of input microchannels connected in fluid relation to said first inlet, said plurality of input microchannels comprising at least a sample input microchannel and an elution input microchannel.