DNA detection by a strand reassociation complex

Selective detection of nucleic acid (NA) comprising amplification (primer extension); binding products to a capture probe (CP); separation of CP-bound extension products and measuring label in the probe, is new. Selective detection of nucleic acid (NA) comprises: (a) amplifiying at least part of NA with two primers (one for each strand), where at least one is labeled, to form an extension product (EP); (b) binding EP to a capture probe (CP), forming a hybridization complex; (c) separating the EP-CP product from non-bound components of the reaction mixture; and (d) measuring the label on CP. CP is designed to bind to the strand of EP that also hybridizes to the product formed by extension of the labeled primer. An independent claim is also included for a reagent kit for detecting NA, containing at least one labeled primer and at least two different immobilized or immobilizable CP, where the primer and CP bind to the same strand of the extension product.