In one embodiment described herein, a bodily fluid separation material is provided comprising a formed component capture region and a bodily fluid pass-through region. The pass-through region has structures with a reduced liquid leaching quality relative to than the capture region, wherein during separation material use, bodily fluid enters the capture region prior to entering the pass-through region. Optionally, a bodily fluid pass-through region has a reduced amount of liquid leaching material relative to than the capture region.
