Alkylamines improve detection of compounds in biological samples fixed with formaldehyde

A method for analyzing one or more compounds from a biological sample crosslinked with formaldehyde, and the method includes (1) contacting the sample at room temperature with a sufficient quantity of selected unaalquilamina from the group comprising ethylenediamine, ethanolamine, and propylamine to release at least a portion of the crosslinked compound and thus improve the accessibility of one or more compuestospara analysis, (2) substantial removal of alkylamine from the sample prior to the detection step, and (3 ) detection (of) compound (s), wherein the compounds are nucleic acids.