Biodefense, forensic, clinical, and food analysis applications require the ability to extract nucleic acids from varied sample types, while eliminating inhibitors that may adversely impact PCR.  We have developed several classes of protocols and devices to address this need.  The LiNK cartridge is a fieldable collection and sample preparation device that uses a chemically treated paper to bind PCR inhibitors in the sample and produce PCR-ready DNA. The Affinity Magnet protocol uses magnetic beads with custom-synthesized non-antibody-based chemical coatings to concentrate target bacterial DNA, cells, and spores from the sample matrix; it has been implemented in a set of cartridges for application in a field setting.  Liquid-liquid extraction (LLE) is a protocol that is capable of rapidly separating nucleic acids, proteins and inhibitors.  These devices and protocols have been exercised on a wide range of biological targets, materials and sampling venues, and have been shown to provide effective and easy sample collection and purification in both laboratory and field settings.