Abstract: The invention provides a system and methods of multiplexed, solid-phase isothermal nucleic acid amplification. In various aspects, the invention uses a microfluidic device that includes a field of actuatable microposts in a reaction (or assay) chamber to enhance fluid flow, mixing, and hybridization/capture efficiency in a solid-phase capture assay. In various other aspects, the invention uses oligonucleotide primers immobilized in a field of actuatable microposts in a reaction chamber of a microfluidics device for capture and amplification of target-specific nucleic acids in a sample fluid. The invention provides methods of producing a micropost field (array) on a substrate for printing of a capture array (e.g., an array of primer spots). The invention also provides methods of printing an array of capture spots (e.g., primer spots) on the substrate surface of a micropost field.